I'm probably in the minority, but overall 1h is fine.
1-handers have the potential to glance more because of their lower initial damage. That is also why 1-handers benefit the LEAST from PS. Since PS is percentage-based, 1-handers get the worst return on a PS investment.
You can't really increase 1-h damage, 'cause that would bring them too close to 2h and pole and would make 1h WAY the hell overpowered.
The thing with 1-handers is you need fantastic footwork to do well. Shielders live and die by their footwork, much more so than the other classes. Most shielders also stack str, which I think is the worst overall way to play a 1-hander. Either balanced builds 21/18, 18/18, 18/21 (my personal fav) or builds that more favor agility are the way to go. Shielders just don't get the return when stacking PS. Not to mention the fact that carrying a shield already makes you slow which is bad when you're fighting people with weapons way the hell longer than yours.
At 6PS, it is INCREDIBLY rare if I glance and when I do, it's entirely my fault. Hell, I have an alt with 12 PS that I rarely glance with. I have another 1-h no shield alt with 15 str that also rarely glances. It's all about footwork.
I do think it's easier to do well as a 2-hander or a pole user, but a REALLY good shielder (of which there are only a few) will tear the shit out of an enemy team like no other.
In my opinion, the only big problem with shielders is cut damage. Cut damage is way worse than every other damage type. It hits 1-handers even more so due to their lower initial damage. Still, my sword is my primary weapon and I regularly tear the hell out of str crutching plate users with it. If the devs changed damage types to be more effective vs different types of armors, it would help balance out the damage types a lot.
Also, another place where I'm in the minority, I think the new 1-h stab is FANTASTIC. WAY better than the old stab. You can get the stab off much quicker and can stab much more reliably now if you know what you're doing. It's way better than the old stab where people saw it coming from a mile away.