Re: Suggestions welcome, River Rock exercise
It is a little hard to tell exactly where all the tones fall as the image looks like it might be unevenly lit. The left half looks darker.
Perhaps this is where opaque white could be used for a few highlights. I am not a fan of this approach. I like to save my whites and as you suggested it might be too late for that.
FWIW I'd just make more paintings. As Mike says we are all critical of our work. I bet when you review this piece in a year you won't be as critical.
Adamphotoman AKA Grant “There is nothing worse than a sharp image of a fuzzy concept.” ― Ansel Adams
Any Camera any Lens