Earth 2160. I did try, but I just couldn't bring myself to care about any of the characters at ALL. I cared more about my light tanks than about the commander of my military unit, with the strangely pseudo-RPG inventory system with different types of armour and weapons. However, it is to be commended for making the hero units blander and less interesting than your basic cannon-fodder unit which dies when you sneeze on it.
Company of Heroes. I know it's amazingly well-received and all, but for some reason, I STRONGLY prefer the Codename

anzers series, especially the first one.
Project Aftermath. It was just.....
ehh.
Space Siege went this way after a while. I just got bored and stopped playing.
Space Trader could've been an interesting diversion, but it..... wasn't. It was annoying to play.
Saints Row 2 sounded like a fun and interesting game. Then I played it. Somehow, it was..... I don't know, it lacked something I think. I just didn't care about the game at ALL.
Armies of Exigo. Too "classic", too old-fashioned, I guess. Very reminiscent of any RTS game from roughly the decade centred on the turn of the millennium, 1995-2005. Just not interesting.