Why not positional variation?

[Koen G]

Whenever I look at the nitty-gritty of Voynichese text, I can't help but feel like some glyphs should be (positional) variants of each other.

* final glyphs have a flourish: Eva- s, n
* In a series of i-minims, the last one looks like EVA-n
* In a series of c-shapes, the last one looks like EVA-s
* EVA-q could be the preferred shape of EVA-y before o

There are also other things, like if you have a series of minims that is not preceded by [o], the first one looks like EVA-a. And I'm sure there's much more like this.
I'm also sure all of this has been remarked many times before. What I don't understand is that some of these features (like [n] being just another minim) have not been adopted as the default approach yet...