I've printed a still-darker green over the previous layers.
I fixed that wobbly tree by applying some ink with a brush after printing. I'm not sure if this dark layer completes the picture; I might print a near-black over some of the tree trunks to bring them forward. (There's a bit of glare on this photo; the trees are darker than shown here.)
But previous experience shows that it's the final layer where it's most likely that everything will go wrong...
I'm going to put this print to one side while I think about what to do. Usually when I do that, I lose the linoblock, which makes the decision for me.