Here are a few thoughts and suggestions.
1) What makes combat fun...? Now I'm not exactly sure of the age rating this game is for, but blood is realistic when it comes to combat. What the game lacks in combat is the satisfying spray of blood when struck, a crimson blade once the deed is done, and some type thwak animation slash sound.
2)Ever played fallout where when you fall you break your legs and your arms get hurt bad enough they are impaired? Why not have this in xsyon? Of course you would need a good way of repairing your limbs these could of course heal over a certain amount of time or could require some type of medacine. When you break an arm you can no longer use that arm to swing a weapn and have to change hands! When you break a leg you have to limp away and let it heal before you can move right again. Rest heals limbs faster than using them.
3) (just a shot in the dark, may work may not) Want realism? Why not add an additional meter aside from health. Why not have a blood meter? When your in a real fight and you get cuts all over you loose alot of blood, which does regerate over time. Why not have a blood meter that falls when you are hurt, because eventually we'll get something like pain killers but that doesn't restore lost blood, as your blood levels go down you get weaker and weaker. This defeats the Wow tank that just keeps healign and fighting for hours. The blood meter goes down slower than hp and lower blood levels lower comfort as well. But you can also do blood transfusions to raise your levels.
4)When someone comes back to life, shouldn't there be some kind of sickness. 1/2 stats make less quality stuff for a while. A chance for some type of brain damage where you forget somthing about a skill and loose a level?
5) Make and explorer skill where you draw a map of an area as you walk through it and it sketches in player made things from "arch" skill and trees and such. Then this map you make can be copied with certain materials in hand inta a physical item that can be traded to another player. But don't worry these map are not automatically updated! The world is always changing and so are maps once the traveler remaps the area so they are still relavent for trading in the future! There are many people who travel the world out there reward them for it!
More to come....