Quran quotes tend to be written in Arabic, which is written right-to-left; writing this left-to-right is awkward.
Also, increasing the size of the font would help with readability.
We have a kinda-sorta solution for Hebrew on Judaism and Biblical Hermeneutics. There aren't currently plans for a virtual keyboard for Arabic because we are waiting to see how the Hebrew keyboard is received.
One thing that made supporting Hebrew a lot easier was that a user wrote a userscript prototype. In fact, HodofHod's script is more featureful than the official version. (Thankfully, it's possible to use both at the same time to compare them.) It should be possible to fork the Hebrew keyboard and alter it into an Arabic keyboard. I can't make any promises that Stack Exchange will integrate it, but such a solution should help users who are willing and able to install userscripts.