Well, there is Shock Pulse: Piercing Orb plus Arcane Orb: Celestial Orb, but it is more party oriented as it is more effective with somebody helping you to round up the mobs and tank them for maximum AoE effectiveness.
Frost is hard, since most Cold Spells sacrifice damage for utility. In terms of AoE, Meteor: Comet is a big hitter, but requires positioning and almost impossible in hard kiting. Blizzard has low damage, and Ray of Frost is single-target.
Skane, I know Hell mode isn't the kind of place to start experimenting, but do you have any viable alternative builds to using Disintegrate+Hydra ? Don't get me wrong I love it to bits, but if I don't start mixing things up it's going to turn boring very soon
(Basically, I'm sick of seeing orange and purple all the time )
Spectral Blade is a dubious choice unless you specifically gear/skill/rune your Wizard for melee. Melee Wizards do exist, but the build is pretty specific in order to be effective.
Diamond Skin is pretty much a keeper as a panic button.
Hydras are love. Pretty much a staple for any Wizard. Arcane is the most versatile, while Venom is best for Bosses.
Blizzard depends on how much kiting you want to do. With the Temporal Flux passive, Arcane Hydra will slow enemies too. Blizzard is also pretty low damage, and may not be the best choice for group-play. It is popular with soloists though. Blizzard also has the worst coefficients for Life Leech/On Hit.
You are lacking an Armor spell. If you want to channel Disintegrate longer, you may want to consider Storm Armor: Power of the Storm. For pure defence, Energy Armor at the later levels will serve you well, with either the Force Armor rune or the Prismatic Armor rune.
For more damage, there is also Magic Weapon: Force Weapon or Familiar: Sparkflint.
Generally speaking, Wizards will usually choose two attack spells to focus on, two defence spells, and two utility spells. It is quite hard to have more than two attack spells until you have good gear to compensate for the loss of dps from the utility spells.
Another popular defence spell is Teleport: Fracture. People pair it with the Illusionist passive so that the CD is a non-issue. If you can afford the passive, it is something to consider.