That doesn’t sound like a bad idea. It would make discovering the existing PS/CSP/SAI compatible shortcut/canvas input schemes (and the fact that those are two separate things) easier. And it was previously suggested to make new/additional default workspace(s) (UI layouts).
Other apps like Blender and Inkscape have setup dialogs similar to this, which also let you choose for instance the color theme.
Icons are a bit complicated, if I remember correctly, I’m not sure how possible it is to make them easy to change.
The UI colors are changeable by switching theme in Settings->Themes,
but there’s no UI to make your own theme. (There is a decent if imperfect plugin for that, though: Plugin: Theme Creator Extension )
Font and font size can be changed with Configure Krita->General->Window->Use custom interface font.