Whats a good number of corruption to farm?

As title says. I'm looking for a nice go to number for corruption and can't seem to find anywhere that states it. Is there higher potential for LP the higher you go? Or more exalts on an item? Is there "diminishing returns" at a certain point? Right now I'm at 350 corruption and it feels pretty much the same as 200. I'm level 98 so the xp isn't all that important to me anymore