Im sure others will elaborate more, with pics, probably. So, just quickly, you mentioned the angled pastern. Shoulder should match that angle. A nice sloping pastern makes for a comfy, easy to sit trot. Lots of TB's have it, some too much.
You want a shorter back, not a horse who has the head in the arena and the butt still in the stall
Good walk, nicely stepping under himself, prints of the hind in front of the front ones.