Hercules might make a fun guest star too (considering Freg and Snowbird have experience with him)....I'd also like to see a crossover with the Avengers at some point (involving both books!)...Bendis need not be involved. Maybe another Fantastic Four team-up?
EDIT: Actually, Captain Britain (and Meggan?) could be an amazing guest appearance. That way Cap Brit gets more exposure (does England still play some role in Canada?).