24/15 is my build of choice. You got to keep in mind that the low weight and length makes sure the movement speed decrease from carrying the weapon is very minor. Especially for 1h, cause they get affected less anyhow to compensate for the heavy shield, which you don't have. You can find this information in WaltF4's posts. I'd say 5 athlethics as swashbuckler is a bit faster than 6 athlethics with a Danish.
You should get athlethics until you feel the speed is decent enough. For me it was at 5 athlethics and I then put the rest in strength. You need to maximize your damage. 27/12 and 21/18 are builds that would probably be okay too, 15/24 and 18/21 would seem crappy to me, I have only tried 24/15 and then 24/18 at lvl 32 though. Especially with the low armor all that athlethics is just a complete waste. It would make some sense if you would go for a pick or a mace and need the speed to get in range. 5 ps with low armor and a sword, I wouldn't do it. I used 5 athlethics with a brigandine and it's fast enough.
Do not max wpf, your animations will be awesome and I get regular complaints about my speed with 4 WM. 3 is easily good enough. I do not recommend light armor, it has never really benefited any melee build. More armor equals better performance up to a point. Survivability is important, especially because you're an up close and personal class in most situations and those get teamhit a lot.
Whatever you do, get a 100+ range sword and learn to rightswing. It is the only way you'll even get to fight in regular group vs group situations in battle. Although you don't really have the enormous group vs group things with lots of pikes in NA that we see in EU, partly the reason why I like playing on NA, my class works better there.
