I'm inclined to agree with Daisuko here, even while I haven't had time to do any experiments on my own. 250 * retention chance (as a fraction) would put the minimal gain at 25 points for HM chests without title bonuses (0.1 chance) which coincides with the previous value.
It looks like a
huge boost for achieving Unlucky if you can gain almost ten times the amount of points per key as before.
Edit: broke a pick at 96% retain rate, got 240 Unlucky points as expected. I consider this issue resolved
