Re: Shower Pan
I think I'd steer away from tile too, myself.. some minimal fairing and a good nonskid should do the job, but don't make it too harsh since, as a shower obviously people will be barefoot on it.
By the sounds of it the curvature may preclude the removable grid....
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"