Despite the efficiency of separating the tasks, they both had waiting room with anxious people waiting their turn. In the driver's license place, that meant a huge room with people sitting and bouncing their feet/legs, kids running around squealing while playing with foam swords, mothers rocking their baby's to calm them down (either while sitting or walking around - the latter I found often meant they gravitated towards me, since I always tried to find a quiet, isolated spot away from the other people waiting). That place used the same system as most other DMV's I've visited, where they have different letter/number combination codes, so you really don't a clue how soon you're wait will be over. In my mind, that just adds to the anxiety, and fidgeting, of the people waiting, and exacerbates my misophonia triggers.
On the other hand, the vehicle registration place was MUCH smaller and although there really wasn't room for people to sit and wait, they had a simple "deli counter number ticket" system, with a counter clearly visible on the back wall. I knew exactly where my place was in line (I was #76 and they were on #60 when I got there), so I was able to walk to the drugstore next door to take care of a few errands, walked back and they were on #68 so I checked out another adjacent store, and just waited in the beautiful weather outside. When I saw the counter read #74, I walked inside and was called within 2 minutes. Less misophonia trigger stress and a more pleasant experience.
I do think that DMV's like the first one should have a system like in Nevada where they text you when your turn is coming up, and you can send "s" (status) texts to get an estimated time, so you don't have to wait in a crowded room of anxious people for hours on end. Maybe one day more states will follow their lead.