Yes makes great sense thank-you Carl.
Last time I did an incline was decades ago for a branch line to serve a heavy Graham farish pannier tank with metal bodt, so weight was likely an advantage for traction and can't recall the gradient but no going over tracks to contend with.
I've read 1/50 is OK if no long trains and/or have run up.
Thought! Never ran double headers on DC but maybe a steep hillside switch back would be a nice feature I can do.
5 coaches eh. Allowing 10 inches per coach your passengers will want a 50 inch platform.

My last layout was max 3 or 4. It seems to be a limit for us in OO unlike N guage.
I think when I track lay, I'll defer point motors and scenery so I can run and tweak design with hindsight of running.
Dave