I am not feeling much love for the shelves myself. If you could have the shower head above the shelves, then maybe. I would be worried about a leak in the grout at some time or another.
You could run the shelves towards the commode and do a blind system for towels. Use a door to match the new cabinets and have a roll out/ pull out. I think I would still put my plumbing valves at that end, so I could access shut offs for them.
Just kickin ideas. What ever you and yours decides will be fine I am sure.
If you don't take pride in your work, life get's pretty boring.
Rule of thumb is if you donít know what tool to buy next, then you probably donít need it yet.