The clearest and easiest-to-read font I have seen is the one used in Mamady's book. In essence, it uses the basic idea of box notation, but presents it in much more readable form. (The person who created the font clearly knew something about font design and readability.)
The font includes notation that allows you to express three-, five-, and seven-rolls, flams, muffled slaps, and so on, and it has an arrow that marks the starting point for patterns that do not enter at the start of a cycle.
You can buy the font from Michael Peters
. Cost is €45.00. The license permits personal and non-commercial use, so you can use it for yourself or for class hand-outs, for example, but you can't use it to, say, publish a book or as the font for a rhythm collection on the web.