For excellent single target damage, go Sonic (stacked -res). Ice is a good mix of aoe and ST and stacks slows with snow storm and freezing rain. Energy would require you to position your toon in order to avoid complete chaos in teams, but it should be much fun.
I'd consider Dark too. Tentacles are just lovely to keep the baddies in FR radius and once you get a Gravity Anchor Proc in it, it becomes a godly power.
Also with Dark you're able to stack stuns with Thunderclap and Darkpit. This works particulary well if you manage to get ~40% ranged defense - you cast FR on a big spawn, they'll use ranged attack and most likely miss, then you hop in and stun the heck out of them.
Now, my Storm/Dark is not exactly impressive when it comes to damage (no build up and all) but then again I'm a defender - even though I play as an offender all the time.
@False Fiction - Virtue / Defiant
Current projects - [Glaciologist - Ill/Cold Troller] [Cloudshaper - Storm/Dark Def] [Harald Wartooth - Elec/Psi Domi]
Ice/Storm has 3 AoE rains that slow, knockdown, and kill anything in the kill zone. Plus you get a nice single target hold for pesky targets like sappers.
Triumphant Defenders Forever
Psylenz FF/Psi, ArticQuark Storm/Rad, Symon BarSisyphus Bots/psn, Max VanSydow Thugs/Dk, Cyclone Symon Bots/stm, Blue Loki Ice/Cd, Widow 46526
HelinCarnate:OMG it is so terrible. I have the option to take 3 more powers but no additional slots. Boo F'ing hoo.
Going for Ice/Storm.
Tried Sonic/Storm briefly. Worked pretty good but I had forgotten about how the fog horn SFX drive me crazy.
Tales of Judgment. Also here, instead of that other place.
good luck D.B.B.
Working on a concept character where Storm will be the secondary, but I'm at a loss for a primary.
What sets have the best synergy with Storm? I'm leaning towards Cold, Sonic, or Energy for theme, but I'm open to ideas here. (I know Energy will have all the knockback, but I'd like to team, ever. >.>)
Tales of Judgment. Also here, instead of that other place.
good luck D.B.B.