First, go out and shoot. Do not worry about having the perfect gun for the division.
Anyway, if you are going to buy another gun to make major in Limited or L10, a 40 would make more sense, due to higher capacity than a 45 in the same platform. If you reload, load the 40 ammo lower when you are shooting production, and up to major for Ltd/L10.
Again, go shoot a match before making any more purchases.