Don't worry about angles for shaving.
Most of the old instructions that came with razors say "almost flat on the face" so that's pretty low :p
https://sharprazorpalace.com/shaving...ng-basics.html
Horn is a natural material that can want to go back to its natural shape or can be heated to a new one. If the scales are bent but the razor closes true then it may have a warped spine or bent tang and the scales were shaped to the razor.
If the razor closes to one side then the scales have changed shape & can be heated to reshape them. There's a few threads if you search.
https://sharprazorpalace.com/worksho...rn-scales.html
https://shavelibrary.com/w/Fixing_warped_horn_scales