What are the group dynamics and emphasis of the trip?  Fish a lot or more travelling, setting up camp and covering ground?  If you're fishing a lot I would have 2 tandems and a solo and take turns with the solo.  If you're moving around a lot and in the canoe for transportation more, I would recommend the 3-person and tandem and take turns duffing.

A solo canoe will probably not keep pace with a tandem - but a kayak would.  I don't kayak but I have before.  Took me about 2 hours to get the hang of it, keep a straight line and stay dry.  It's like riding a bike right?