Well we got pretty hard water so limescale builds up everywhere (if id just let the plate dry it would be mostly white) therefore the idea to maybe used distilled water - IPA seems to get rid of all the remaining water pretty well through. Just drying it with a towel does end up with at least some white spots/areas on the plate. (Might be worth some experimentation how limescale does actually effect print quality - yea overthinking it again.) Fatty finger prints are pretty obvious causes for surface defects.