hi i have just a short and i think easy Suggestion
why don`t you set the lvl Limit to, perhaps 100.
the Xp would like always increase for the next Lvl (i think they double)
and thats it
Players would have a Little Goal to work for
and they will get Tokens for every Lvl up like its already is , so they can bye keys or use them for other thinks
... i think this is not that hard to Change ...and you already battle Players with 1.000.000 Xp ,it will have no effect on the battle System ...

thanks for reading

yes