For what it’s worth I’d +1 to default for Option 2.1: Colors based on the direct outcome of performing the action
Perhaps adding configurable options for warning/coloring/prompting on deletion would be prefferable as the coloured examples @amilica shared struck me as alarming/distracting
I’m +0 for option 1. My only problem with it is that if you want to drop the action labels to get more horizontal space (for power users) and you have a toggle action (e.g. lock/unlock) where the on/off icons are similar (it’s usually the case, with only a small variation) then it’s hard to identify the toggle state (color can compensate the lack of label in this case, for those that are not color-blind of course).
+1 for option 2.1. I fear that option 2.2 may lead to some “inconsistencies” (the same action is sometimes colored and sometimes it isn’t) that users won’t understand right away.