I've heard about Terracore before, I wanted to sign up but I was disturbed by the fact that you need 20 Hive or even 30 Hive at the beginning (I think) to start playing, it seems logical to me that you start free, and then if you like the game you start playing.
I've heard about the second one now, but what do I know, I'll have to see what it's about (through your link, clearly), but it's true that I've never been in a guild for the game, maybe it will be an interesting experience :)