Creating a Monte Carlo simulation is a bit beyond what I can do, but conceptually, I think it is fairly clear: there should be a tactical role for every type of character build. The problem is that a pole user’s defense isn’t as high as a character that uses a shield, and their attack can’t keep up with a dual-wielder.
The opportunity seems to be a strong attack that affects multiple opponents, which the engine comes very close to achieving. There are traits that specifically benefit dual wielders, and others that only benefit archers or priests. A perk (halberd mastery?) that increases cleave chance 10% per level (max 3) would allow for a pole user that would hit two opponents 50% of the time, and be tactically quite useful on the front lines of a party. Alternatively, every level of pole weapons could increase chance to cleave by 1%, which would become fairly substantial after 15-20 levels.
I’m sure there are other options as well. The point is that a pole user should be able to do something that a melee user cannot, and at present there doesn’t seem to be a scenario where this is the case.