JB is addictive, but the odds are pretty high that if the player count is high, the warden and CT's are going to more toxic, leading into a bad experience.
TTT is fast-paced. It's fun but with a lot of players, RDM chances will be high and your T round will probably get ruined.
Minigames is always fun. There is not a single time where it isn't. It's never full though, so you may get bored of it.