Nice idea. Minsc should grant a +2 bonus to butt-kicking. Priests like Anomen and Viconia could grant slow regeneration in lieu of Cure Wounds spells. Edwin might add spell slots or decrease casting time by 1. That sort of thing.
And while we're on the subject of the SwaP script...
Having more than two or three NPCs in the party gets troublesome. In particular, pathfinding and movement speed (i.e. there's a limited supply of boots of speed, and it takes a while to gather them besides) are frustrating with too large a party. I rather like the Solo-with-a-Party script in its current incarnation as it eases combat management. Some form of travel convenience would be quite nice, though. Maybe give them an invisible avatar with a small bounding circle then add a Contingency (opcode #232) to teleport to the PC every round, like a phase spider?
Ideally, though, I'd like the option to shove my party members into my pack, like familiars, only still letting them interject and so forth while carried. It'd take a black belt WeiDU ninja to convert the NPC scripts into a format that could pop them out of your pack for scripted scenes and such but otherwise operate from within your pack, though. Soo that won't be happening. Ever.