I planify to come back playing C2C. I gave up some months ago because a nasty bug (should be resolved with help of a member of your team). But I probably will begin a new game.
I played some others 4x, trying to discover some good things. I played Beyond Earth a little, and even people don't like it, I liked. Probably it should be better with some mods.
I played also Endless Space 2, and that a very good game. But I stopped it because game breaking bug. So I will not play it soon, waiting it's patched.
Actualy, I play Master of orion. I have a lot of other 4x to play more because I didnt play it very much, like age of wonder 3.
But nothing is as much deeper than C2C i have to admit.
Also I like auto-battle. Master of orion (the last one), it's better to use manual battle, but I don't understand how to use it well and it's not turn by turn (real time with pause), so I don't like. ES2 is better, you just choose a tactic card and it's all done. Age of wonder is more easy to understand with manual battle. But honestly, it take too long time to do it. I really prefer full auto battle when playing a 4x. There is too many battles.