Struggling with Plum Tree — would appreciate advice

I want to be honest: I'm not getting great results with Plum Tree and I'm not entirely sure why. late frost damage to blossom in exposed positions has been a recurring problem despite my attempts to address it. I've been focusing on thinning fruitlets in early summer to improve individual fruit size based on everything I've read.

blossom spectacle in spring before any other ornamental value is there in glimpses, which tells me the plant has potential in my conditions. I have it in a fan-trained shape on a warm boundary fence which might not be ideal. winter pruning while the tree is dormant showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.