Just finished the final mission, and it was everything I hoped after seeing the trailer in the direct! NG+ is a very cool challenge as well, as I get big for my britches thinking using high level towers on early stages will be cake, and it's totally not haha.
I did have one crash in the first mission where you don't get any money for destroying ships, early teens I think? But it only happened once and I was able to make it through the rest of the game without it happening again.
Also, I have to assume there are technical limitations in the way, but I would die for a free play mode.
Seriously, I love this game. Definitely gonna remember it for next year's awards!