Reminds me if the idea I had a while back about wrapping or taping your erection before pumping to inflate the glans overall. I still want to give this a go but I can imagine the skin pinching effect one would get at a psi above 5 psi hg. The only other option would be to buy one of those “clone a willy” kits, lube up your pump cylinder with Pam, disconnect the quick-connect piece and plug the hole, then go about the instructions and mold your cock. Then when the mixture sets you can reconnect the quick-disconnect piece, clearing any obstruction, and blow the mold out of the cylinder. After that you bore a small vent hole the top and cut the base off if you wanted to even out your baseball bat or disect the head if you wanted to grow your mushroom, although you might have to figure out a way to fix the mold to the tube with doublesided tape or something. From what I’ve seen in the pictures the molding material appears so be very stretchy which would allow for vacuum expansion and maximum comfort. No more skin stretching friction half way through.
These were just a few ideas I had and havn’t been tested yet.