Yeah... weapon DPS is super tricky. It's hard to make comparisons cross-class as what's "good" fluctuates a lot.
As far as staffs go, someone posted earlier about a lvl 23 Rare staff they had that did 151 DPS. I think they said that was un-runed, which sounds insane to me.
I haven't tinkered with Fire Mine yet, the damage looks great, I was just concerned about the AoE on it. Fire Wall actually does pretty solid damage as well and has the advantage of being persistent and allowing me to cover a lot of ground with it, so I opted for it instead. I feel like Fire Mine would be awesome if you regularly grouped with an AW that could drop Abyss for you.
Anyway, yeah. Ele is a ton of fun. Most of the mage classes are great actually, Keeper's really the only one I haven't gotten that attached to. I'll admit, part of it is because I don't really want to listen to her dialogue.