Regarding ST -
ST:TOS - sentimental favorite as I watched it growing up, I still feel it has some of the strongest core ideas if you like big imponderable ideas in a sf setting that usually isn't dealt with very deeply as Kirk needed to fight someone and get his shirt ripped.
ST:TNG - Working my way through this again. I remembered enjoying it, but also feeling like a friends description as Star Trek Intergalactic Taxi Service wasn't wrong. Be curious to see what I think now. First season is actually better than I remember it (damning with faint praise?)
ST: DS9 - Only saw maybe half the episodes because the local station bought it to bury it in the early morning (2-3 am). Seemed like it had a lot more story to tell because it dived deep into one area (but at the expense of the best 'adventure into the unkown' that other series offered, though they did manage some of that even with the stationary locale).
ST:VOY - Why didn't Paris die in the first episode? Or before the first episode? I'm not sure I've ever really given the series a fair shake because I hate the character of Paris so much. My memory is that too much time was spent with the characters bickering but my memory cheats (if not out and out lies) at times.
ST:ENT - goofy. But sometimes enjoyably goofy. I don't think I saw the last season other than the final episode.
ST:DIS - Haven't got to DIS yet.