Just going to throw my two cents in here to defend truck pushing.
First of all I've started to try Starcraft 2 recently and I've learned that there's a thing called cheese. This is where one player goes for attempt to end the game quickly by attacking their opponent first. This is usually an all in tactic as if it fails you will be considerably behind.
Truck pushing is a form of this cheese yes but that being said it is still something that should be allowed within the game and shouldn't be considered a game breaking mechanic.
Well, generally when you cheese an all in, it means that either you do tremendous amount of damage finishing a game or having a huge edge or you basically concede.
When there is NONE risk and reward, there is a problem right there. Right now the thing is slow as fuck, but remember that lights vehicles arrive at 3:00 so theres no risk on pushing up to this point. 30-45s earlier you might expect an AT nade or nothing from USF (unless Elite).
Mind you that it's an extra pair of eyes and allows OKW to alter the terrain to improve retreat paths.
I'll give the truck it's prior stats (including building crush) if:
-You make it cost 200mp and remove it from teching
-Make truck health correlate to building health. Right now it will go back to 100% once it starts building.