The easiest tab system works like this.

Diatonic

2 = blow the 2 hole
-2 = draw the 2 hole
-2' = draw the 2 hole with a half bend
-2" = draw the 2 hole with a full bend

Chromatic

2 = blow the 2 hole
-2 = draw the 2 hole
<2 = blow the 2 hole with the button in
<-2 = draw the 2 hole with the button in

This is the system I use. It is easier to use than other systems that use more charactors

I have used the quotation marks for bend notes, but I eventually decided to
use the flat and sharp sign for bends.
One b for half tone flat
Two b's for full tone flat,
and the same for sharps using #.

I think your system is better than a lot of the ones I've heard tell of.
Someone was using the slash marks ( / ) for bend notes I think.

I only use that mark for the beats in a measure.
In songbooks, they use arrows, and for bends; they show a curved arrow.