Auto-save feature.. Corel painter 18 Has problem with crashing when it has been running for more than 4 or 5 hours, auto save would effectively solve that problem. I don't save in the middle of what I'm doing because I get so engrossed in what I'm doing.
corel doesn't care about preserving your work. I used to hit save every ten to twenty minutes in my painter days (less often on a more reliable, but no longer supported painter IX.5 version.)
clip studio paint and the yesterday's update to paintstorm - which will be the closest package when comparing overall experience to painter - have auto-save function. artrage doesn't crash nearly as much. those will be your best options for now and, most likely, next few years.