I hated lvling RDM but ymmv, it's just so similar to 4.x and I didn't like that either. My sub is running out and won't be renewing for now, so I'm not done with lvling, WHM/MCH/BRD/NIN left, I'm keeping NIN for the rework anyway, and I wanted some classes to do beast tribes leveling with without wasting the xp so it's fine. Overall I'd say my old favorites are still my favorites. I like the new MNK and BLM for DPS which have been my go to since ARR, SCH is still my favorite healer and that was my original main and PLD is still my favorite tank which again is what I played back in ARR, so not much has changed, they're all still solid classes. I didn't care much for most other classes but DRG was pretty nice, I'm really liking the MCH rework, DNC is alright but feels a bit meh depending on RNG so while I leveled this first I haven't played it that much once capped. GNB was really nice however, better than DRK/WAR imo.
Usually take a break until x.4 or so but with BLU getting an update in 5.1 I might resub for that, I'd hate trying to do BLU stuff when it's not new, after a few weeks no one runs shit anymore and it fucking sucks, unless they make learning primal skills less retarded, that'd work too.