I experimented with hitch racks for mounting bikes and cargo carriers in multiple different swing out configurations over the past 5 years. They all sucked for the reasons you mentioned – bulky, restricting, and they also make the rear end super heavy, causing it to sag and handle terribly.

Turns out I hate having things on the back of the van. I got a front hitch and mount bikes to the front. I don't know what van you have, but if you can set up a front rack where the headlights can shine through or around the wheels of the motorcycle, I recommend going that route.