His head seems a bit long to me but then I think most heads on the new art is too long or muzzles too big. He also doesn't seem drafty to me. I know they aren't typical draught horses but their bodies are still a bit thicker

I agree the head is quite long, my lease horse I'm Pretty sure is a half Irish draught and Marwari and her head isn't very long, although shes a crossbreed the characteristics of the head just dont match up at all the head looks more Lustiano than Irish Draught

agree on slightly too long head (and maybe because of that too skinny muzzle) and about overall body thickness. My friend has one and he's definitely on the thicker side.

I agree about the body not being that drafty. Where I live we have a lot of Irish Draughts and Irish Sport Horses and they are a chunky breed.

Echoing what others have said already: a little more chunk, a little less face.

My very first thought was that this is quite a long face for a pure ID.

 I also kind of agree about them often being chunkier, though I've seen some that were lighter like this, so the face bothers me much more. 

The face is very long for a pure ID. It also doesn't look chunky enough, especially the legs. 

Show ready IDs are often overweight so not a good example, but even hunting fit ones are still very stocky. This looks more like an ID cross. 

If you thicken the legs, it may give the overall look a much ‘heavier’ feel. The body itself does seem like it might be drafty a bit (more like a warmblood) but the legs are definitely more thoroughbred-like. By thickening them up (in particular the upper parts on the front legs) it could make the draft look much more drought-like.