Andor
First Post
This.
Especially when subraces are involved... so you cant be a mountain dwarf if you are a Cannith? Backgrounds are the logical and mechanical option for House membership in addition to a normal background. So in Eberron House Membership Background should be a bonus background anyone can take. Just like joining the Harpers or Lord's Alliance.
Actually that's a good point. The Adventurers League Rules provide an additional mechanic for representing both Houses and some of the other groups in Eberron, the faction rules. That seems like the proper place to put House Membership/Affiliation. The Mark could then be covered by a feat and/or Background.