Just a few thoughts:
If the hand setting is loose, that's not because you've used too much grease. Too much grease causes a mess, but not looseness. Looseness is because the cannon pinion is worn from there NOT being proper lube previously, and now it needs to be tightened.
If it overbanks, that is a fault in the safety mechanism of the escapement, which is made up of a roller with a cutout for passing (the one with the jewel, on single roller; the small one on double roller) and corresponding pin or dart, and also the general condition of the jewels and pivots that keep the safety parts in their proper places with respect to one another. When you service the escapement, check it for safety - try to pass the lever to the wrong side throughout all the balance's positions. Concentrate especially on the positions where the fork and jewel are interacting. In a correctly functioning escapement it will not be possible to move the fork to the wrong side in any situation.