Hi there! Thank you so much for playing and awesome review, I really appreciate it! =^_^=
My original plan was to make each tower specialized against 1 type of enemy (it would hit the other types of viruses but it would give way less damage), I think it would have helped fit even better the theme... However since I had 9 types of enemies in mind when I started the project I gave up on the idea because I was afraid of not having enough time (little did I know my game would end up with 5/9 enemies so I should have tried to rush and add that mechanic, oh well ) >_< But I'll definitely add the things you pointed out.
Once again thanks for playing! \(^_^)/