The current experience function is hundreds of lines of code which takes into account everything from a mob's total attacks, damage they do, procs the mobs have(dif procs have dif exp bonuses), hitroll, hit points, armor class, bleah bleah bleah bleah bleah bleah bleah bleah bleah bleah bleah bleah...
This function has been continually adjusted for the past 25 years in order to give us the result we desire. Any change to simplify this function to a few lines of code would have drastic effects on every mob, area, and continent in-game. Unless one of our programmers finds a needle in a haystack, there is not one algorithm which would closely match up to our current mob values. I completely understand that it's possible to come up with AN equation and we have done so in the past, just not anything we felt comfortable with. No system would be perfect though which is why having room/area bonuses, mob bonuses, etc, would always be needed.
I'll be honest, I am perfectly fine with removing the current equation and trying to come up with something. Just like I was fine with coming up with a universal algorithm for all skill based damage based on class order and other variables or the idea of a point eq system(Teker). Changes like these normally alienate at least half our player base, if not more which is why they are normally done with a pwipe

I think we all hate the idea of caps(eq, exp, etc_ and wish the game was balanced without needing them, that is not currently the case though. Caps were the quick and easy solution to many huge issues...
There are two major changes on the lines of these which come to mind and went in-game as configs so they could be turned on and off until we felt comfortable with our adjustments(not including the addition of 4 new classes); new armor class system based on tenths rather than whole numbers, new timing system from tics to continual. Both systems were eventually adopted with player input and are live today. Both changes changed our game drastically, way more than we ever anticipated and were done when we had probably 10 active Immortals and 4-5 active coders.