rogue 5/assassin 10/shadowdancer 5, until the expansion, then rogue 20/assassin 10/shadowdancer 10. And there are useful skills in the shadowdancer class by lvl 5, such as shadow evade, which gives you 50% concealment, i think, which is really handy for melee, but rocks for ranged attacks. Sniper material then.

relying almost exclusivly on sneak attacks is a mistake. There are many opponents that are immune. This is why its preferable to continue on with a character that can dish-out the damage and has sneak attacks as a bonus. In this case several have suggested the Assasin as the 3rd class. This may be acceptable IF your ONLY utilizing ranged attacks against strong opponents. If however you utilize melee fairly often then it is FAR preferable to select a BlackGuard instead of an Assasin (particularly if utilizing a weapon that can simulate the Assasin's paralyzation feature).

Blackguard would be good, as well, and the hide is there for the shadow dancer, but, I am running the assassin char now, and initiative is every bit as important. I may not be able to get an actual sneak attack, but i can flank, and attack, and flank and attack. Rogues can be effective in melee, if you use strategy, and the ghostly image ability rocks, with concealment, and dmg reduction. Ofcourse, blackguards can use heavy armor, so they can just tank, but finesse is cool too, if you can pull it off. You won't be able to finesse a dragon, but there are a lot of creatures, and NPC's, that you can.