jungle items needs to be a cut below the standard lane items because they also include the jungling bonuses.
runic echoes has to be weaker than ludens, otherwise it would be ludens PLUS jungling bonuses
cinderhulk has to be a bit weaker than sunfire, though some people could argue this because of the % hp bonus, but honestly i think the % hp comes from the fact that it's better if it doesn't have either armor or m.resist because that way then you just have a decent chunk of hp and can then build AR or MR depending on the enemy team comp
warrior is a slightly weaker ghostblade without the active component
now, FINALLY devourer is a somewhat weaker wits end, but even then, devourer gets this absurd passive that applies a SECOND set of onhit damage every other attack, which makes it stronger than wits end by itself and then, on top of that, multiplies all further damage from all future items that boost ad or also apply on-hits. That's a bit too much man.