18/18 is terribly underrated.
18/18 with a warhammer does a ton of damage, has knockdown, a practically unbreakable shield, can take hits and moves pretty quick.
I don't think the point investment to 7 PS is worth it as 1h damage scales terribly with PS anyway. You're better off using a MW weapon, speed bonus and held attacks as you'll get more out of those damage-wise then just flat PS increases.
Only when you get to 8 or 9 PS does the damage really start to creep up, but then you're turtle-slow and you're still way out-paced in damage by 2h/pole users.
Still, a 27/12 1h no shield build is pretty fun.