I would agree with @KrudlerTheHorse. He makes a lot of strong points.
I love me some Crimson Bat, but I agree the team build is not ideal. Here is one you can use to great success early on.
Soothsayer***/Valkyrie/Crimson Bat/(Blue Dmg Dealer)
Another Crimson Bat is ideal but before I had my second bat I did alright with Rowanne in that slot, or Shadow Cat works well and covers Purple as well.
Feel free to check out my Team Build Compendium for some ideas too.