I've had a blast in the hotseat games. The diplomatic stuff makes a huge difference, and the challenge of fighting human opponents (and ability to cooperate with human allies) makes it worlds beyond single player.

The flipside is, as Ramses noted, it moves more slowly. Time limits for turns helps, but I don't know of any that gives less than 24 hours per turn, so you could still be waiting a while.

With stricter rules on time limits and admin enabled games (allowing gms to change a password if a player vanishes without a word, or even change a faction from player controlled to AI controlled), games run more smoothly now, and the Kingdoms campaigns run a lot faster.

I'm not sure if any are currently open, but there's nothing stopping anyone from making a new one, and players drop out of them sometimes( I think the first grand campaign has had some of this) allowing new people to take over their factions.