Two handed weapons seem relatively uncommon compared to 1-handers and missile weapons, at least early on (maybe this changes later in the game). Bare minimum I find three or four 1-handers for every two-handed weapons I find.

Not using a shield already has drawbacks, especially in the early game, I don't see why the weapons should be a lot less common as well. From a realism standpoint I can't think of any reason why two handed weapons would be so rare.

Potential balance implications: You'd be more likely to kill early monsters in one hit, though several race/class combos can already do that all throughout the early game. You'd also be less survivable than you would with a shield so maybe it's not a big issue?