Just looking for opinions.

Knights of the Nine, for example, felt pretty strange as a mage or spellsword, or as a less-than noble warrior, even. Does the story in DG make sense for all character types and dispositions? I'd like my first play through to make sense, rather than to feel like fingernails are scraping the chalkboard in the background...

dawngaurd is for warriors and stealth characters imo, it has a mainly paladin feel about it with its blunt weapons and holy spells

The vamps seem to be for mages, the vl form is a magic monster, and the armor from them gives spell regin.

Thanks! I appreciate the response.

Yeah the Dawnguard is basically the Paladin Faction.

dawnguard= warriors
vampires=mages/stealth

I'm very excited to take my Cleric character into the Dawnguard. He's unarmored, but he fights with enchanted maces and Restoration spells. Sounds like he'll be a good fit.

I think it lends itself perfectly for an Archery style. You get some pretty good gear

I've done both sides with varying character concepts.
No matter who you are, you don't need to wear their armor or clothes or wield their weapons. Just do what makes the most sense for the character.