Upgrading Dark Distortion to adept III is a no-brainer, even a must. Frozen Manacles and Freeze you will be using quite a lot in your 20's, so upgrade those to adept III if you can, but you don't have to. Mine are adept 1 and do just fine. Upgrading Steal Breath at 27 to adept III is also probably worth it for lowering the poison and disease mitigation. That'll be more important as the mob resistances start to get higher, plus it does DOT. You won't get another lower noxious mitigation spell until around lev 40 if I am correct.