4E or Pathfinder.
Definitely not 5E.
I've started playing in a full Pathfinder campaign last Sunday, while GMing my Pathfinder Beginner Box game (and 4e, and Labyrinth Lord). I'm also a player in a Labyrinth Lord game, so I have 5 campaigns on the go right now. Oh, 6 counting my online 1e AD&D game!
Playing the full Pathfinder game reminds me that 3e/PF is a great game to play, and a pain to GM!
I can see myself having loads of fun with my Ulfen Cleric PC in
Rise of the Runelords, but I really don't think I'd ever want to GM full Pathfinder. Meanwhile 4e is great to GM, and fun to play if the GM doesn't dick around with 3-hour slogfest encounters.
So, looking ahead now,my current plans/hopes are:
1. GM my 4e D&D Forgotten Realms campaign all the way to Epic 30th level, 22 levels to go at ca 3 fortnightly sessions/level = 66 sessions, around 140 weeks, so ca mid 2015!!
2. Play Pathfinder - Rise of the Runelords, it's fortnightly and if it goes all the way that'd take it ca 35 sessions, 70 weeks plus say 5 off for vacations would take it to early 2014.
2. Intermittently GM my Pathfinder Beginner Box game, I'm adapting the core rules to take PBB classes up to 10th level, like to see some domain rulership type stuff at 9th-10th.
3. Intermittently GM my Labyrinth Lord game, maybe. I may decide to drop either it or the Beginner Box game.
4. Play Labyrinth Lord. Loads of fun, great GM.
5. GM a sci-fi game! I'm desperate to get to use all my cool sf minis. Still not sure I have the right sf ruleset; might even need to go back to Savage Worlds. Trouble is that SW has player-side stuff, but very little GMing tools to actually create and run a game; but I do have Traveller: The New Era adventures that could be Savaged and used in a Buck Rogers type setting. Maybe from March 2013.
6. GM my online AD&D game.