Hi there.
You are making a good argument on options. Initially I narrowed it down because if you don't you have to choose a result for each action everywhere, which was too time consuming.
Also, I am concerned player will just spam every action everywhere.
I might use this option only for weapons. I wanted to give the choice between gun (and gun+), laser whip and plasma bow, each with pros and cons. So for instance, for an ennemy, you would first select your weapon then fire.
I would combine this with tricks like I have used: the crack on the wall after the boss can only be opened if you save and go back (since you spent all energy on bombs on the boss), you won't find it in the natural course of the game.
So to sum up: I would like to go for a hybrid solution between current implementation and your suggestion.
Regarding RNG, there will be plenty of way to mitigate it.
Thanks for the detailed comment !