Struggling with Japanese Maple Bonsai — would appreciate advice

I want to be honest: I'm not getting great results with Japanese Maple Bonsai and I'm not entirely sure why. root bound decline from leaving in the same pot too long has been a recurring problem despite my attempts to address it. I've been focusing on wiring branches during the growing season while wood is flexible based on everything I've read.

seasonal change including blossom, foliage colour, and bare winter silhouette is there in glimpses, which tells me the plant has potential in my conditions. I have it in a bright indoor shelf for tropical species only which might not be ideal. autumn colour on deciduous species before leaf fall showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.