I tried playing online once, but the game kept crashing (maybe due to my slow internet connection). Sometimes, I can't even start the game.
Wingael, surprisingly, allows me to start very well, but my friends constantly criticize me because I spend too much time flying back and forth with fakes, killing zombies manually. The point is that from level 7, you can safely attack archers without worrying too much that they will shoot first.
There are indeed difficulties with wood (on Veteran difficulty, I don't play with friends on Hero difficulty), but somehow I manage to keep up (I only upgrade archers, I don't build unicorns).