The best ones I have personally played were 11 Rogue 6 Barb 3 Bard, 18 DL, 1 Rog, 1 Barb (can replace one of them with Warlock as well), 18 Barb, 1 FvS, 1 Warlock.
The last one I did was 18 DL, 1 Rog 1 Barb. This one gves you access to more feats and the higher level tactical DC feats which...