First off, I have a point, despite being unable to read AR10 with BG. I know some people can but I'm basing this on myself.
I can't read AR10 with a background. I can read it without BG.
I can read AR7+HR with BG. (AR 9.8)
I can read AR6+HR+DT with BG. (AR 10+?, or 9.6 - 9.9 depending on formula, but this is irrelevant because of DT)
I can read AR8+DT with BG. (AR 9.6 or thereabouts)
Imo, the main problem with AR10 is that the notes spend more time "fading in" than staying solid, making the use of followpoints on backgrounds very important.
The difference with DT used with AR values 8-9 or 6-7+HR is that DT chops the fade-in time on the notes. This makes it readable on BG. But AR6+HR+DT is supposedly faster than AR10? How?, I can read AR6+HR+DT with bg, but not AR10, simply because of fade-in.
IMO AR10 fade-in time should be fixed when osz2 comes around. No alteration to the absolute time of the note's appearance, just less fade time, more solid time
And these are just my opinions, so yeah, not going to feature request
Tell me if I'm wrong and why, I am actually interested in answers.