Hi William. I'm pleased that you prefer the pitch notation for 22-edo that has always been its standard Sagittal notation. It is shown in figure 8, on page 16 of
http://sagittal.org/sagittal.pdf. Although to keep the size of the article down, since it was originally published in the paper journal Xenharmonikôn, we only gave the pure-Sagittal form. Here's a sample of the mixed-Sagittal form of the 22-edo notation, which you would be well aware of, but I include it for the benefit of other readers. It shows successive pitches horizontally and enharmonic spellings vertically. I've shown the Sagittal symbols to the right of the sharps and flats here, which are to the right of the letter name, as is conventional in text.
22-edo:
D D
D
D
D
D
D
E
E
E
E
E E
E
F
F
F
F
F
F F
But when it's used on the staff, the Sagittal would be to the left of the sharp or flat which would be to the left of the notehead. e.g.


O
And you may prefer to put the Sagittal to the left of the sharp or flat in text as well, e.g.
22-edo:
D
D 
D
D 
D 
D
D

E
E 
E
E E
E 
E

F 
F
F 
F
F F
F
I don't understand why you refer to

and

as 1/2-apotome symbols. In general they do not have a meaning as any particular fraction of the apotome, and in 22-edo they happen to correspond to 1/3-apotome. Their general meaning is the 5-comma (syntonic comma).
I agree that you should not use

or

in notating 22-edo pitches, particularly if you intend it to be read by anyone else. I don't recommend using them in naming 22-edo intervals either.
In JI, an 8:11 from C could be notated C:F

, and as a composer thinking in terms of 11-limit JI, you might notate its closest 22-edo approximation that way privately. But when communicating with others who may not think that way, and particularly when communicating with a performer who shouldn't have to learn multiple symbols for a single step of 22, it should be notated using the symbol for the lowest prime comma that will do the job, namely C:F

.
Using

would be even worse, because it would point in the opposite direction to the required alteration in 22-edo. In JI, a 5:7 from C could be notated C:G


, but in 22-edo it is C:G


.
There is already a separate thread on 22-edo interval names, in the "Interval and Chord names" sub-forum. You can see Cam Taylor's scheme in it here:
viewtopic.php?p=47#p47