0 to F gives you 16 - it will be easier to use with midi, which has base 2 amount of divisions

I mentioned it because I genuinely enjoyed drum programming on the MC500 MkII; I still think its interface is the fastest and the best for this (not so much for other things :). 10 velocity levels are enough for drums generally.

How about a hex nibble or byte so you don't have to draw individual x's and .'s (this leaves out velocity entirely)

Then maybe add a binary file format for storage efficiency. Give it a standard file extension so we can recognize the files, maybe '.mod'?

Can't wait! We live in exciting times of limitless opportunity! The future is now!

... and that's the story of how come there's only one programming language.