If you ask me, in order to lessen number of greatswords, Longsword, HBS and Bastard Sword should be buffed. Hell, I'd even buff Katana at this point.
Longsword +1 cut +1 pierce
HBS +1 pierce
Bastard +2 pierce
Problem with this is that most americans won't agree because longsword has different status on their servers. Perfectly reasonable, considering the fact that they have STR builds and greatswords are indeed slowish with those builds. That's why they use longsword.
But that doesn't mean that longsword is OP, it's merely good weapon and a quite lot worse than any decent greatsword (I've tested this on my char). Same goes with Bec. Every EU player knows it's rubbish but on NA it's still good because ages ago great players used it...
Also one handed swords deserve serious buff, speed they have can't compensate for animation advantage twohanders have. Every greatsword user will backpedal stab and if you don't have enough ath you'll have issues to get in facehug range. Even then, there's kick to help them. Because all of that, one handed swords deserve damage buff which should put them on bastard sword's level, damage wise. Put some penalty when they are used with a shield if you think that's easy (but actually it's not) but please buff those swords.
With 5 PS, 6 ATH and MW KAS with 26 pierce stab I glance all the time on horses. Longsword with 25 pierce stab never glances, even with 1 wpp...
Btw. just because Kastu owns people with his MW onehander and agi build doesn't mean one handed weapons are OP. Kastu with greatswords have like 50-1 scores every map...