​​​​​While the OP did ask for a rack that doesn't touch the bike frame, and I do think wheel-tray racks are the way to go, in my experience being paranoid about the wheel touching the frame is overrated.

When I thought about it I realized that I've had a frame break while riding the bike and it wasn't a huge deal I just coasted to a stop and got off. In contrast, if the front wheel breaks, you're going down faster than you can react and it's going to hurt. Squeezing the front wheel might be dangerous if you weakened it by clamping it to the rack.

With a wheel-tray rack anything that touches the frame is mostly just to keep the bike from bouncing around. I suppose there's a chance you could knick up the paint in the frame, but like with the saris freedoms rubber attachments even that seems unlikely.