I am fixing a lot of bugs of RTL languages. More improvements coming soon. I aim the site here to be nearly perfect :) And it will be in the software by default soon, and it will reach Commons and other wikis by the end of this year or the start of next year. So if you have feedback or bugs, please say! (Btw, I will look at the issue you said, when I have time.)
I fixed the reply count in mwr:91528.
As for the lang="fa" dir="rtl" attributes, I can add it, but is it needed? Are there problems with it?