Yes the original was just about the chart. Mike posted the #1 chord for C7 is F and unfortunately I tried to explain this and drove the topic in a different direction. I apologized for that.

I think this thread shows the danger of asking for theory advice from users when the OP has very little theory background. All we as users can do is guess how much the OP knows about theory. Learning is much better when one learns from a book or video and not piece meal from users IMHO. Asking questions about what they are already learning in one thing but trying to learn theory via users is another.

I would much prefer keys in Ab over G# or Bb over A#.

I think I would have a problem with a no key signature song when F, C, G, and D are always sharped. Lots of wasted ink when all one has to do is to make the key signature E. That must be a nightmare when transposing for other than C instruments.

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware