Another meaning to adding a hook in the picture? It's a good photo to work with but I also feel that the composition could use extending/adding a little more at the bottom, just to give it a little breathing space.
@edavison & @alsart, folks, if you wish, all the research that needed to be done on this topic of preparing panels for oil painting has been done here already, look for thread named; Priming - Oil Painting, Acrylic Gesso, Plaster of Paris, Traditional Gesso, Rust-Oleum etc., posted by @ Kaustav in April 2017, 4 pages total.
I ran into such a situation painting my recent portrait, the more I looked all the more I saw and understood as well, mostly in the color department. I think it's about, keep on trying/practicing until you get to some satisfying level that you can real work and even master eventually. So here it appears to me that maybe you over worked it, I prefer the previous step above, looks similar in style and as well painted as your most recent flowers. The challenge is to learn to recognize when to stop and pull off while recognizing the value in that is the key point.
I am glad you all like it so much, I think it's quite a fantastic little publication myself. I have had only several (6) months reading and studying, and letting things sink in with me, still learning, very powerful stuff for any artist. One of the very best I've read without a doubt. What do you do once you begin to learn from such a great artist and you get one statement that says, "he never left anything to chance", I believe this to be a great secret to making great paintings and it's hard work. The scary part is stepping up to the plate and paint as he did or even just try, if you know what I mean! This going to be one very interesting painting challenge ahead, looking forward.