Monsters Vs Zombies - TD

Tower defense game in early alpha. One level demo to get early impressions.

Your jobs is to summon monsters that will take down the zombie hordes on your doorstep. These monsters are able to cure the infected. They will also game experience over time and can eventually evolve into more powerful forms. Each monster has their own strength and weakness. Using them in combination is the key.

I would love to get impressions on monster types and the game in general.

Also some ideas for naming the unit types would be helpful.