I wonder if it'd be easy to alleviate the current exp system outside of abyssea and just mimic it for every single zone while allowing the same chests to drop to build those lights but if you leave the zone you lose your light builds of course and exp can scale up in certain zones up to a maximum. The highest lvls of the mobs can remain the same and maybe have it where you don't need to fight the same type of mobs to build this exp too and you also can get rid of some chests like TE and you definitely don't need cruor chests/drops per mob unless the chests gets replaced with 250-1k conquest points, imperial standings, etc. depending which region you're exping in.