Still, it will make it harder to fill all of the gaps with only 3. With 4 it'll be easy to build an incredibly well-rounded amalgam, especially if we're getting everyone's experience, not just one "mind" like in this tourney.
And while I think we all have at least a couple 'unknowns' that we're planning on picking, eventually we're going to get to the last round and if we have 4 per person the 15th or 16th person will have to pick Jubilee or Toad or something similarly horrible. I'm not planning on being that person, but I think that with less people in our amalgam it would make each pick more important and competitive.
-DM