For an alt, dps probably doesn't matter much. Go for playstyle. I created my shammy with the intention of being elemental at 90 (but had enh heirlooms, so leveled up that way). Switched to ele around 85 when the heirlooms gave out, and.... hated it. I was easily just as 'powerful', but the playstyle change did not agree with me. I love enh for the instant abilities almost across the board. When I was faced with actual cast times as elemental I went nuts
I'm still adjusting to melee in raid situations - I've always favored ranged, but enh playstyle > my fear of melee thus far. And I still have an ability or two that lets me 'cast' from ranged for those times when I can't be toe-to-toe, so it almost feels like a melee/ranged hybrid (no, it really isn't).