I think that all parties in this discussion must include Student, just because we all know he's going to show up anyway. Anywhere there's a gathering of heroes he's bound to show his blank-piece-of-paper face, and it's just easier on everyone to accept this as fact.
I'm not sure about the rest of my party, but I'd like Assassin and/or Bounty Hunter on my side. We don't see a lot of their personalities besides playing straightmen to Kogal, but what I do see is exactly the type I'd like to have around me during an adventure. I kind of want to include Hunter as well, just because I feel like he deserves to get to be in a group of actual interactive people and not just NPCs, but then if I do I fear the party being unbalanced with two long range fighters and a ninja dude. Who am I kidding? Despite his name Hunter would probably rely on his maxed out sword skill. Then as another "You deserve this" arrangement, I'm calling on the hero girl from Ch. 4, to give her the reverse harem she so clearly deserves after putting up with those bitches for as long as she did. Huh, I guess that fills out the party. At 5 people (or should we be counting ourselves for 6?) I can't think of anyone else to add.