I am here looking for a SharePoint UI / branding of SP Site.
And this is only applicable who have already done this successfully (you should share some examples please)
So, it is a thought to move away from the SP Classic theme or site to a NEW, FRESH and CREATIVE SharePoint Site.
If you have done so, that would be great and we will discuss further.
I am not sure though, probably you will need to be an expertise to Designing HTML, CSS or Bootstrap may be..