Originally Posted by
DragoonWraith
Change "enhancement bonuses" from "enhancement" to "inherent". This goes well with the idea that they're not magical, and allows it to stack with Greater Magic Weapon. Make yourself a +5 Greatsword, and your Wizard buddy can cast GMW on it to make it +10. Probably still lackluster, but at least it's not still +5 and missing +4 worth of additional abilities.
I assume that despite being non-magical, the enhancement bonuses still count towards the +10 limit? Can you make a +10 weapon, just literally straight up +10?
Also, I'd suggest making the enhancement/inherent bonuses give +x to damage and attack. That makes them a lot more attractive.