Jun'ichi Haruta as Hiryu Tsurugi/Change Dragon
This is a big one for me. When Toei was having trouble casting the part, they were just going to hire reliable JACtor Haruta as Tsurugi. I'm a huge fan of Haruta's, and while Tsurugi would have most likely had a ton of awesome out-of-suit action scenes, I just can't picture anyone but Haruki Hamada playing him. Haruta SHOULD have played a Red, but I don't know if Tsurugi would have been the best match. Haruta would have been the oldest of the five cast members (he would have turned 30 early into Changeman's run; Hamada was 23) and maybe seem a little too mentory, whereas Hamada was younger and you could believe him in Tsurugi's more hotheaded, stubborn, intense and impassioned moments. (I think a lot of Tsurugi as we know him was shaped to fit Hamada.)
Because of Hamada's casting, Haruta ended up joining the Juspion cast in the role of Mad Gallan, who was originally supposed to be played by Shun Sugata. (And thank goodness for that, too, because Sugata probably wouldn't have gone on to play Tatewaki in Janperson and he's awesome in that.)
Shirou Izumi as Hiryu Tsurugi/Change Dragon
Izumi auditioned for Dragon, but was thankfully cast as Yuuma/Change Pegasus instead. I don't think he's quite Red material, but he's a perfect fit for Yuuma and just nails the part.
He didn't specify which role he auditioned for, just that he auditioned. (I think he'd obviously have been Hayate/Griffin if he was cast.)
Yutaka Hirose as Jin/Red Flash
Someone at Toei used their head and realized he'd make a better villain, and a legend was born.
Hiroshi Kawai/Kazuoki Takahashi as Kenta/Black Mask
The role was intended for Kawai/Takahashi to play. (He instead joined the cast of Metalder.)
Kenta Satou as Burai/Dragon Ranger
It was interesting to find this one out, and it's the main reason I wanted to do this post. Now, as a Changeman freak, I love that Shirou Izumi, by playing Burai, has such a big, important role in Super Sentai's history. He's a good actor and one of the reasons I was even drawn to the Burai character. But I always felt he held back, you know? Or maybe he just wasn't comfortable going full villain turned tragic elder hero. His casting always puzzled me and I've long wondered just how they chose him or who else could have been up for the role...
Well, supposedly in the pamphlet for the Gokaiger-Goseiger Super Sentai 199 movie, it was revealed that designer Tamotsu Shinohara, when designing Burai's costume, based the design off of the person he was led to believe was playing the role -- Turboranger's Kenta Satou. This shocked the bejesus out of me, because...Kenta's an awesome guy, he's one of my favorite Reds, but I really can't picture him playing Burai, especially the early pissed off version of the character. (He's also the same age as Geki's actor, Yuuta Mochizuki, when Burai NEEDED to be a bit older. Heck, Satou's a few months YOUNGER than Mochizuki.) So, finding this out has made me appreciate Izumi even more, even if I can think of a couple of other ex-Sentai heroes who, in my opinion, would have been even better.
Keisuke Tsuchiya as Ryou/Ryuu Ranger
I talked about his a couple of times before. I guess the thinking in casting him was "Hey, do you guys dare me to cast a blander guy than the dude who played Goggle Red?" Thankfully, someone at Toei ignored that guy and replaced his pick of Tsuchiya with Wada. And it wasn't even just auditioning -- they even went as far as sending the guys to wardrobe and started shooting promos! So, this casting was THIS close to happening! Scary.
Keiichi Wada as Kazu/Kirin Ranger
What a waste that would have been... Wada's the Last Action Hero of toku. Can you imagine him being wasted as Kazu, stuck with obnoxious turtle storylines?
Hideki Fujiwara as Yuuji/Oh Blue
The role was offered to him, but I guess he turned it down. Which is probably good, since Yuuji's supposed to be cool and Fujiwara's a big goofball, and always looks like a tween.
Joe Odagiri as one of the Tatsumi boys in GoGoFive
It could have happened, if he wasn't so stuck up. Hard to picture him as anyone other than Nagare/Go Blue, though.
Masayuki Deai as Ryouga/AbaRed or Ban/Deka Red
Deai auditioned for both. I didn't really like him in Boukenger, but I feel like he's the kind of guy who needed a better show. I don't think he would have worked as Ryouga (Kouichiro Nishi was kind of perfect for that show and role) and I think he would make a better Houji than Ban.
Tsuyoshi Hayashi as Nakadai/Abare Killer
I've mentioned before how I don't really like what Koutarou Tanaka did in the role of Nakadai, but Hayashi would have probably been worse. He's just too damn young and too stiff of an actor.
Mitsutoshi Shundo as Nakadai/Abare Killer
Now THIS guy would have been awesome. He made for a good villain in Ultraman Nexus and I think he would have given off some classic Sentai villain vibes in Abaranger. (He reminds me of Shinji Yamashita/Shunsaku Kudou from Fiveman.) Shundo's the appropriate age that the character SHOULD have been and is actually menacing. He'd make a villain you could be afraid of. I guess he'd have been a little TOO intense for how soft Abaranger ended up treating Nakadai. They really pussed out, man. (Could you imagine Shundo singing Dead End Game? Get out of here with that crap.) Shundo also had auditioned for the role of Himeya/Ultraman Nexus before being cast as the villain of that show.
Naoya Gomoto as Ban/Deka Red
Ended up guest-starring in an early episode of Dekaranger instead. So, who's this guy and why am I bothering to mention him? Because just about anybody else would have been a better Ban than Ryuji Sainei.
Mayu Gamou as either Jasmine/Deka Yellow or Umeko/Deka Pink
Going on to guest star as Succubus and then later joining the cast of Kamen Rider Hibiki, Gamou had auditioned for one of the heroines. (She would have made a good Jasmine, IMO. I like Gamou, she deserved more than what she got from either Hibiki or Deka.) She also auditioned for the role of Rejewel in Abaranger.
Shoko Nakagawa as Umeko/Deka Pink
Sentai super-fan Nakagawa is said to have auditioned several times for Sentai Pinks, but came closest in Dekaranger. (She eventually guest-starred in one of Dekaranger's later episodes.)
Yutaka Kobayashi as Captain Jean-Luc Marvelous/Gokai Red
Kamen Rider Gaim co-star Kobayashi was a finalist for the part before deciding to drop out. Which is kind of good, because Marvelous needed to have that likable, rascally quality which I thought Ryouta Ozawa pulled off. (If Kaito/Kamen Rider Baron is any indication, Kobayashi ain't exactly likable.)
Jiro Chiba as Takeshi Hongou/Kamen Rider
This one's interesting to think about, because Kamen Rider fans have long wondered if -- as awful as it sounds -- Fujioka's accident HELPED the show. Because what if the show stayed as dark as it was and it ended up getting canceled? Takeshi Sasaki's Hayato/Rider 2 was popular and brought levity to the series -- you can't dismiss his involvement in the show's continued success. Would the show have been doomed if Chiba had been cast?
Shun Sugata as Kazuya/Kamen Rider Super 1
Before he ended up playing ZX, he had auditioned for Super 1. He's said he was bummed that he lost the part, but...c'mon, he wasn't a good match for that dopey Rider. He deserved something more than ZX, though, IMO.
Hiroyuki Watanabe as Kazuya/Super 1
When he was cast as Ga-ou in the Den-O movie, Watanabe -- known to most toku fans as Kouga's dad in GARO -- mentioned he had auditioned for Super 1 way back. It's surprising he never ended up playing a Rider -- I guess the franchise being dead for a majority of the '80s is to blame -- but like Sugata, I don't think he would have worked as Super 1.
Yutaka Hirose as Koutarou/Kamen Rider Black
Hirose would have made a great Rider. He would have been a great Black if the series had stayed the same tone as its premiere episodes, but...can you imagine Hirose riding down the road, befriending every crying kid he saw? Hirose hopping into video games to save kids? Hirose pulling over to the side of the road to sing "Ore no Seishun"?
Kazuhiko Nishimura as Koutarou/Kamen Rider Black
He could have worked, but that means he wouldn't have been Jou/Yellow Lion, and I feel like he's a great fit for that part. And Tetsuo Kurata's such a giant, it's pretty hard to imagine anyone else as Koutarou, really.
Toshihide Wakamatsu as Kouji/Kamen Rider J
He was considered for the part, and thankfully someone must have had the thought "Hey, let's not waste an actor like this in this turd of a movie." Wakamatsu would have made an awesome Rider, though.
Masaya Matsukaze as Godai/Kamen Rider Kuuga
I previously have said that I don't think what Odagiri did in the role was all that special, that a combination of writing and production talent was what made Godai and Kuuga what it was. I said ANY actor could have played Godai and it would have been the same. Well, Matsukaze kind of proves me wrong, because he's just...not that strong of an actor. There's a reason he moved on to voice-acting, me thinks.
Noboru Kaneko as Godai/Kamen Rider
To this day, Kaneko desperately wants to play a Rider, and he auditioned for Kuuga. He's more Godai-like than Matsukaze, but...maybe a little TOO soft? (It's funny to think that, despite how really young Kaneko always looks, he's actually OLDER than Odagiri...!)
Shou Tomita as Takumi/Faiz
As much as I love his work as Yukito/Abare Blue, I remember being so frustrated in 2003 at how bad of a pick Kento Handa was as Takumi, and how someone like Tomita would have been better. So, imagine my surprise to find out he actually DID audition for Faiz at the same time he auditioned for Abaranger.
Some genius at Toei wanted Handa because they thought he looked like a young Takuya Kimura. (I do remember reading that. How sad is that? No wonder the quality of casting has gone so downhill for toku. "Kento, forget that you look 12 years old and are anorexic and a wooden actor -- you remind me of one of our over-the-hill celebrities, so here's a show that you will be completely incapable of shouldering!") My opinion of Handa has changed somewhat, though. When I rewatched Faiz last year, I was surprised that he wasn't AS wooden as I remembered him being, but...still, there's a ton of other actors who would have worked better. You certainly don't look at Handa and think "street brawler."
Masayuki Izumi as Takumi/Faiz
He was great as Kiba/Horse Orphenoch, and since everybody in that show got to be Faiz -- Kiba included -- no big deal. I don't think he could have pulled off Takumi's bad, stand-off attitude, though.
Jun Yoshida as Dai/Shaider
He went on to play antagonistic Poe in the series, but auditioned for the main role. I don't know how that would have worked out -- I think Hiroshi Tsuburaya is a strong actor who did about as good as anyone could have done with such an underwritten role -- but I do think Yoshida could have pulled off being a hero in some other show.