I have painted white trim (casing and base) that has been recently installed. I am looking for advice on what to fill the nail holes with. Keep in mind that the woodwork is already painted. I am also looking for something to fill a few of the miter joints with. (some I just could not get that tight). I used Sherwin Williams Pro-classic waterbased and am looking for a product that I DON'T have to prime and DON'T have to sand since the trim is already painted. Thanks for any advice!