Choosing an engine for a game

So, probably asked hundreds of times before, I already searched for it and know some candidates, but since the oppinions I have found could be outdated, I'll ask again:

I want to jump to game development as a hobbie. I already have a job programming, and know C++ and Java very well (not a guru...yet! :cowboy:). But when I search for game engines there are SO many to choose from.

I'd like to pick one which:

• has a big community of users (for example, PlayN looks nice, but I think lacks of this. just try to google "PlayN push notifications" and nothing will appear)
• is free (since it's just a hobby)
• and would be nice (not mandatory) if it was possible to port to other non-Android devices (iOS, Windows8...). AndEngine looks great, but it is only for Android, and I don't know if Cocos2Dx is reliable.
• extra points if the engine includes multiplayer capabilities or push notifications. I have not found information about this for PlayN, AndEngine or Cocos2Dx, so I guess they don't have these features and aim only for graphics. Moai looks promising here, but I don't want to learn to use it and then discover than the free edition is too limited.

So, I'd love to hear oppinions from game developers around here: please tell me your experiences.

BTW, I'd love to create a Civilization-like game, that's why I'm interested in push notifications and multiplayer. But I'll start with a card game, because I'm just not that mad (yet).

PS: After reading forum rules, I guess this question goes here, in Q&A, but feel free to move it to Android Game development subforum if you think it is misplaced.