You can get nicer 5x5 fonts amd it was not that uncommon back in the day. 4 wide is not too bad if you make the center of M and W just two pixels inset from top or bottom respectively or borrow the spacing column.
Plenty of systems did it like CP/M on the Spectrum +3 and it looks pretty decent.
I remember when these first started appearing in Windows was around the time toolbars became popular.
I think the idea was the most common ones had icons which matched the toolbar button so you could start with the slower-but-more-comprehensive menus and then notice the quicker toolbar equivalent through their matching icons.
If you use LINQ and have ever used areay Contains youre about to find out it's not going to be smooth. They knew about this for a year but decided coercing to span in an expression tree despite it being invalid wasn't worth fixing.
Plenty of systems did it like CP/M on the Spectrum +3 and it looks pretty decent.