My 4e campaign has had a chaos sorcerer from 3rd level. It is currently at 26th level. The PC in question is also a Demonskin Adept (paragon path), Primordial Adept (theme) and Emergent Primordial (epic destiny). The character is a driving force but not a disruptive one: some examples of exploits can be found
here (channelling chaotic energy from the dead dragon Calastryx to enchant items and open portals) and
here (a 1 on an attack roll resulted in Vecna being pushed dramatically over the edge of an earthmote).