1: Agree on the Apocalypse part, I never did get into it, it felt…wrong. I actually did enjoy the UFO-games though, although lacking in several aspects, the combat system was actually a strong point to me. Escpecially Afterlight is a (IMO) very underrated title. I've spent alot more time on those titles then I did on the new XCOM, the streamlining of EU makes replays less fun. Replaying it now with EW though and still think it's a good game.
2: I absolutely love Fallout Tactics, the only think that I don't like is the linearity. But I've played through it several times, and the combat system (again, IMO) is great in RTwP. I tried turn based at first, but like you said it didn't feel quite right, maybe because of the fact that you control several characters and it gets to sluggish. Which is usually a strong point with Turn based… (Controlling several characters, not being sluggish.)
3: I actually think the "Plan-and-go" system in BiA is good, what it lacks in my opinion is the personality and charm of the JA2. And while JA2 is one of my favourite games ever, replaying it today I'm missing some elements that should be mandatory, like to hit percentages.
4: Loved Dark Sun, actually played it the first time AFTER I finished Baldurs Gate. Liked the turn based combat, the lack of information on spells and abilities…not so much.