I like this idea. Would we make it a minimum + though? I think we should make it like a minimum of say +5 or 6 to produce an orb, whatever the cut off is for drops from fire pents vs earth. I worry that this would clog the soon-to-be crowded 38 pents with people who are just there to farm the orbs. Keeping this isolated to fire pents and above would also provide good motivation to make the jump into fire pents ASAP.
Side note, what would we do about the current orb runs? Increase the orbs produced? Turn it into Mil exp shrines instead? Lots of options but if you massively increase the orbs in one area, I could see people just abandoning the current orb runs of level 30 and 40. They are kind of annoying to run but the reward is important and that's why people eagerly do orb runs.
I made a beta salvage mechanic which for now ONLY WORKS IN TEST PENTS. When you trash an item, it is set to give you 20% of items stats worth in orbs (so min +5 stats on item required). Test it, post feedback.