Just a couple of additions to the advice you've already received:
1. As advised above, I'd put 10 points into Warfare for the damage increase, as well as for Crippling Blow, Battle Stomp, and Phoenix Dive.
2. I'd put 2 points into Aerotheurge for Teleportation and Uncanny Evasion, two extremely useful skills for all builds. 1 point into Pyrokinetic for Haste and Peace of Mind wouldn't go amiss, either, although this is easy enough to obtain from gear.
3. You might want to put 1 more point into Polymorph for Skin Graft, which resets all your cooldowns once per battle--very handy! You've got plenty of time to add it later, though, as the skill isn't available until Act 2.
4. As you've already seen, The Pawn is an excellent talent for a rogue; really helps getting you to backstab position. Executioner is also great, but you can't have it and The Pawn at the same time; if you find yourself not needing the free movement, especially later in the game, I'd switch them. Opportunist is a must-have, I'd say. All Skilled Up/Bigger and Better/Mnemonic are good for stat boosts in the beginning, but safe to respec out of them later in the game. Since you're putting so many points in Warfare, Picture of Health wouldn't be bad, either. Someone in the party should also have Pet Pal, but I'm guessing that's already the case with your party!
5. Don't spread yourself too thin with your Civil abilities; you don't get that many points. Persuade/Barter should generally go on the character that does most of the talking. Spread the other abilities out among the rest of your party.
