It's not just the graphical side of things that I see problems. Quite often the AI archers fire flaming arrows against my troops, not just siege engines or elephants. Against Scythia and their archer armies it was unplayable. If you turn off flaming arrow graphics altogether, then you don't know when they are being used--that's not a good solution. Better would be an option to disable flaming arrows period, or at least limit them to specific uses. They have a different effect on morale than normal arrows apparently (although we are left guessing as to what.)

Didz example of using them in a siege vs. the rams and such is a good one of legitimate use. I rarely use enough archers for this to work, because I limit myself to a historically representative number for the factions I am using, and I am very rarely defending stone walls.