On normal difficulty it's a bit too difficult. Enemies respond too quickly and too many bombs are required to kill a building. Add in the delay to restock and it makes more sense just to suicide into the building instead.
Not bad, but maxing out the level seems to be a really bad choice. I still have a lot more missions in the campaign and not upgrades to look forward to, what's the point then? Also the game does take a bit much time wise, and once level progress stops there's not a real feeling of progression.
 "Music Bounce"){kind=icon}
 "WhiteboardWar: ChopRaider"){kind=icon}
 "Balloon Invasion"){kind=icon}