not getting any where

I finished the main missions, but now I guess the only thing to do is upgrade buildings? I have researched a bunch of stuff like the wheel and animals but nothing changed for me to build. I guess there is no more point, I can't expand the area of the clouds. I send explorers out but they don't find anything interesting. I tried to understand the expansion thread but don't get that either. Anyone give me some advise please.  

well it is keeping me entertained. 

You should definitely try to build a second town, that adds a few new things. First you need to research Expansion technology for that.

well it is keeping me entertained. 

You should also look at alpha as a way of gaining experience and learning about how to play the game.  By this I mean that you should think about having at least 3 heroes,  1 who is communality, 1 who is Leaderism and the last one you change their polity at some stage down the line so you will know what happens, if you decide to do that when the game is released.  In one domain learn herbalism and in another go for mysterious cave. Don't follow the same tech path or learn techs in the same order in every domain, mixt it up and see what works for you.  Try going all out for lots of culture and expansion with one of your heroes and going for a big army in another.  By doing that you will get to explore all the elements the game, find out what it really has to offer and it will ultimately help you decide the type of game you want to play when it goes live.