Improvements for the symbol keys

[GoldenChaos]

I'm not sure what's up with the different symbol keys (delete, return, caps lock, shift, tab, alt), but their symbols for the most part look strange and/or need to be positioned properly.

Some, like delete, tab, and alt, are not typically represented by any symbol at all on modern Mac keyboards. Might just be easiest to copy the MBP keyboard design for those keys?

[AndreasVerhoeven]

They mimick the exact key cap as in the macOS KeyViewer.

[GoldenChaos]

Even then, the Delete, Caps Lock, Shift, Return, and Alt key symbols are not vertically centered properly. They're also not using San Francisco's symbol set, it seems? Shot of the KeyViewer:

It's a minor thing but it's been driving me nuts, haha. The native keyboard performs great, though.