2" vs 3" Pans... How to Pick?!?

My income tax refund has come and my present to myself this year is upgrading my cake supplies. My grandmother raised me on Wilton cake pans, but I'm finding they are not really all they are cracked up to be. I've researched and tested and really like Magic Line pans. My issue though is this: If I'm going to spend the money and get all new pans, do I go with the 2" or the 3" pans?

I do a lot of double layer cakes because they are never big enough, so I assume having a 3" pan would be better in my case...BUT, what if I don't want that large of a cake. Is it OK to use a 3" pan and only fill it half or 3/4 full? Does it affect the cake in any way if the pan is not full?

I realize these are odd questions, but really...does anyone know??
Thanks for your help in advance!

 

Thank you. I appreciate the look out for a newbie.

 

Magic Line pans are better in my opinion because of the straight edges and corners. Unlike Wilton pans, they edges are precisely crisp edges...and this is so great for decorating. I prefer their baking as well, as the cakes come out more golden and don't get the dark edges like some pans leave.