Never finished it, but did play some of it: Hellgate:London is a Diablo clone. As a single-player experience, it's barely "ok." Has guns, has at least one scripted combat event moments/quests that you can't avoid (I don't mean act bosses). Gets monotonous, even for a Diablo clone (and I love a good Diablo clone).
I'm kind of in the same boat, because I loved Borderlands, Fallout:NV, Might & Magic's, etc, but I always feel like there aren't many games out there anymore that really fall into what I (personally) really want, even within the hybrid type category you're looking for.

the Might & Magic series is good action-rpg, open world fun. Just FYI, M&M8 allows one to play solo/switch party members in & out, and have dragons in your party. It's the main appeal of #8, since the others were fixed party members set at the start of the game. 6 & 7 are the better games tho, imo. I've never had any problem getting #7 and #8 to run on XP, but yeah, if you're on Win7, probably want the GoG versions (or something akin to that) for ease of access.
Edit: should add that, while the Might&Magic series is 1st person, it's designed at least somewhat around some pause-give orders to party members-unpause concept. eg, party members take turns firing in a 1-2-3-4 type order, not simultaneously. You can battle/run/fire in total real time without pausing (i've done it a lot), but it's a lot more difficult to do that way, especially in certain areas/quests.