My name is Cranky Putz, and it has been three hours, twelve minutes and thirty seconds since I had a regretful thought.
I say “Should” a lo:. I “should” have done this; I “shouldn’t” have said that, I “should” do this etc.
I got to thinking. Using ‘should,’ implies a lot of regret, oh so negative. Using ‘could,’ implies opportunity.
Using should in a relationship (work or personal,) implies authority, Using could, is asking for consideration.
Could, seems a better pick.