People complaining that Lucina is taking up a slot, she really isn't, she pretty much is an alt costume for marth but the developers consciously gave her her own spot because of the slight differences attack wise. If you think, "well if lucina wasn't in then there would be room for birdo!" Well not really. The number of characters in the game isn't decided by how many squares they want to put on the screen- Lucina is a slightly different alt skin, and because of the slight differences they gave her a separate spot.