i like the sound of it
could have a place that expands some of the monsters
say evil bomys , evil bomy soldiers, mages, knights, lords and a king at the end as a boss (put a crooked crown on the lords head :P)
but it could be expanded.
maybe a rare drop key to it from a lord to get to a specific place where the lords. lair? is.
i think if its based off your level it may suit lower levels that know a higher level better.
while a higher level that isnt with other higher levels with be stuck with less exp then would be calculated for a his level i like the party bit but you would need to try and find however many people you need in your party near your level.