I will keep my Twilight 8if I can find evocation +5 on an item otherwise I'll be forced with Nether Orb) but I will change it. It will be Ice primarly so +120 and Electric +138 in the Red slot.
Honestly, if you stay water, you should go Ice/Air. They are both some very good debuffs for the party and for yourself. OR you could think (I did too) to switch to Fire as primary element. Fire/Air looks a lot of fun.
To me, the KD immunity and wings have me hooked to Air but if I wasn't, I'd totally go Fire. DBF and WoF > everything else. If you switch to Fire, the new Fire Dot is AWESOME. 21% crit chance from item + 8% enhancement + 2% from Improved Mental Toughness if you follow my fearts + 5% Magical Training = 36% crit chance on the DoT with over 300 Spell power. Looks a beast to me.