It depends on what you mean by "playable and fun". Havoc is still a screenwide AoE with huge base damage and potential for single target versus non-teleporting bosses, so perfect for grindy trashy ubers like Teganze and Triune. Also pretty good for leveling to 140 in Fauztinville. Although removal of FREE 100% energy from warmage set means it requires pretty heavy twinking, so no 30 seconds Sam kills ssf anymore.