Healing brush tools are slow

Using healing tools in lightroom took 10 years out of my life

laptop: surface book 3

selection: mouse is very laggy, the white outline appears at least half a second after clicking and the whole selection takes seconds. 

actual healing: clone stamp is practically useless, content aware is somewhat usable but result is always harsh, custom selection doesn't really help

spot heal fails 70% of the time and often produce results like picture below a weird bright spot sampling the wrong part.  

Lightroom might as well take this function out instead of driving the users crazy. for the money we're paying we expect something this basic to get fixed after years of complain but I guess Adobe won't do anything.