I'll give it to you straight. It's too simplistic, has no real strategy to it and quickly becomes a chore to repair towers. I only played the first level, I reached a point where I couldn't play any more and just sold towers to end quickly (got some 150k points).

I like the long-click build control scheme. Why not long-click upgrade and repair?  (seems obvious). There needs to be some sort of selection when you build or select a towers.

The game performs well but the options are weird, and so is the default and only resolution.

Personally I find no joy in the only game mode "endless waves", but maybe some people do.