I am starting structural detailing and exploring the mating of end plates and other welded connecting features to structural members.

One needs at least two mates to constrain position and orientation.  Coincident faces gets me started, and where there are no other solid feature relationships I draw a sketch on a face and mate a solid feature to it.  Sometimes I want to mate sketch to sketch but that seems not to work so I cut a redundant hole in one body and mate it to a sketch on the other body.

I don't want the shop to drill redundant holes so is there a better way?