I’d recommend using something like Niri instead of mutter for the compositor as Niri is:

• Extremely customizable
• Meant to be used alone (unlike mutter which is for Gnome)
• Supportive of Wayland portals better than any compositor I’ve tried
• Very modern
• Pretty stable
• Making use of scrolling window management which is, imo, superior to anything else
  • You could force all windows to be floating if you want that traditional method tho

I’d also recommend using DankMaterialShell and simply providing a theming to get the appeal you want. It works well with Niri and provides all the system tools you need for an OS like bluetooth and audio management, application lookup, etc. It’s sort of a stripped down Gnome-shell for standalone compositors but way more customizable.

Then everything else can just be installed WINE apps.