I had not been active for about a year...so I'm a bit rusty.

I'm working on a dwarven TWF assassin build
Starting stats:
STR 16
DEX 14
CON 16
INT 16
WIS 8
CHA 6
2 of my level up points will go to Int, one will go to dex (then i will have 17 with a +2 tome to get improved and greater TWF) and the last 2 will either go to Str, Dex, or Int

I'll either be going:
18 rogue/2 ranger (assassin3)
12 rogue/8 ranger (assassin2/tempest1)
12+ rogue/* ranger/* monk

The way I see it, I have more feats if don't go to 18 rogue, but then I have less sneak attack and lose the vorpal sneak attacks. All tips and opinions are welcome and appriciated!