10.15.0 was scary Should be better now. Recommend CCC backups.
I use mine docked and had to replace 3 yr old dock to get HDMI working again after the .1 update.
iTunes libraries and large photo libraries can take longer or be an issue. Conversion and shuffle of files going on.
I recently did a clean install getting ready back in August which I think was a good idea as had lots of old pieces hanging around over the years and multiple system updates.