Want to watch? That's a simple question.
Everything.
Can and going to watch, now that's a different story.
lol that's always the big problem. Especially as I don't speak Japanese so I can only ever see what's subbed. However, on my "please oh please let someone sub these someday" list:
Changeman and Timeranger - I've watched the episodes of these two that TV-N subbed waaay back when. They're both a lot of fun. Hopefully one day someone will decide to revisit these.
Kakuranger, GoGoV, Hurricaneger and Abaranger - I've seen Ohranger Vs Kakuranger, GoGoV Vs Gingaman, Hurricaneger Vs Gaoranger and Abaranger Vs Dekaranger, and they got me quite interested in these four teams. Also, in the case of Hurricaneger and Abaranger, we would then have a complete run of subbed 'modern' sentai series
'A Day of One Hero' - the mockumentary starring the actor who played Gokai Green.
Kamen Rider Super-1 - I'm not really a fan of showa-era rider shows, but I've seen the KITsubs episodes and I'd love to watch more of this one.
The Kuuga and Agito specials, and the 'Kamen Rider Blade: New Generation' vignettes, as they're the only heisei era rider things I haven't seen.
Ultraman (Ultram
en?) Dyna and Gaia, B-Fighter and B-Fighter Kabuto, Inazuman, and Denjin Zaborger, because they all had something about them (concepts, suit designs etc) that have stayed lodged in my mind ever since I first heard about them, and I'd love to someday see what they were like.