Personally I wouldn't mind the Rattata option but I wouldn't really take advantage of it so it might not be worth it. I don't like the idea of the type change for the Gastly line though. I always liked their poison typing even if it did give em a weakness to Psychic. 

I'm juggling a few character ideas but I should be decided soon. For our older characters, I assume we can give them a little more independence? As in they went by themselves, worked to save their starting money in a part time job, etc?