For the cons that Beastie listed, that's a problem when one works solo in creating everything and needing stuff that are not from other people's work. 2 people may not be enough unless they both are (somewhat) quick, hardworking, skillful, and patient in time. I might be wrong on this, but I think recruiting people skillful with graphic designs, sound effects, sprites, etc., would be helpful, yet, difficult to find. That's a problem when it comes to finding people for help on doing designs and stuff while you code. There are sometimes when some people will be busy with their own situations and it might be difficult when the project will be finished.
We need a team to make but the problem is, we don't know who we are going to pick based on our interests.