I know its an old thread but i wanted to join in =P
 
I agree with Oufo on the towers. Towers take forever to build and upgrade and get slaughtered by damn near anything that can deal damage. 
 
Building mills and bringing in lumber is far more important, nerfing heroes is pointless unless towers get seriously buffed.
 
ATM its like a fork in the road, either build towers and face having substandard lumber and weak hero, or lumber like crazy, get strong hero and win.
 
Basically, unless towers are buffed ALOT (HP, DAMAGE) then the build time kills the use of them. Even then the magic damage towers are pointless. Including frost. I never use it ever. Because it might help a little with weak bosses, but the stronger ones are immune. Then the problem arises, if u spend a lot of time building towers, your neglecting lumber, which u need for the walls, towers, repairbots and mechanics. Hero's are just more efficient.