Ahhhh I love this horse.
He looks like he has wonderful movement and I really like how round and supple he is in the undersaddle picture. Your riding has also improved a lot too, you match each other so well!
I do like how he is put together overall, very typey and compact with a nice shoulder and uphill build. He might grow a bit (16-16.1), but it seems to me that he won't grow any drastic amount, he is filled out in all the right places but needs a bit more muscle in the hindquarters and along the topline. My guy is dutch warmblood and he finished growing at about 7, all horses are different. Plus, he might also "grow" a bit more when he gets proper muscling and such haha. They always look at least a hand taller when they are fit.
Really work on getting him supple and accepting through the bridle and neck, he needs to develop some nice neck muscles to keep his roundness when you have contact. The onlt thing that seem kind of off is his right pastern. It may just be the angle but it looks super long and weak, not a good thing to have when looking at a jumping horse. Maybe try and get some better confo pics of him with his head up and standing really square.
Overall, I loveeee him. He has so much potential and I can't wait to see you guys grow and learn together!
