I shoot with a tab (shot with a glove for a year). Paper tuning works like a charm for me. My release is very consistent, I've chronographed it.
There would be no reason why paper tuning would require a release aid anymore than bare shaft tuning. The reason some might think the release aid is more often paper tuned because lots of shops set up release aid "fired" compound bows by paper tuning because it is fast and very objective.
The couple times I bare shaft tuned was when I was considering cutting the shaft to tune to make sure I could use a specific weight broadhead. I didn't like it because the tune always revealed I needed longer arrows than I'm willing to shoot. So, I went back to PT and flexible weight broadhead choices. Don't get me wrong, the tune didn't change from one method to the other, my alternatives to adjust tune did (but they didn't have to). I use this method with my son, brother, daughter, grandson, and anyone else that needs help.
A friend and gold medal olympian (team in Atlanta) doesn't use either method. He shoots groups at 50-70 meters. He doesn't care a bit how well his arrows fly, just how they group. Of course that wouldn't work for broadheads because the broadhead will overrule (plane) the fletching the first chance it gets from a wildly fish-tailing arrow.
Yes, 6' is fine. Actually, I count the 12" tiles on my basement range 6-8' doesn't make much difference. I place the rack about 1.5 arrow lengths in front of my backstop. A quick way to make a rack is just cut out the bottom/top or sides of a good sized cardboard box. Tightly tape Christmas wrapping paper, butcher paper, etc. over the hole. Slicker systems can be made with PVC pipe and attach a roll of paper at the top. You simply roll out fresh paper, tape it in place, and shoot.