Thank you for starting yet another Morgan thread, so that we can sing the serenade to the breed!
I would like to add to the wisdom of other COTHers above that you should not be worried about what he was like before.
In my experience, Morgans take a long time to mature and behaviors that can occur at four, five, or even six, will often disappear at around nine or ten (provided, handlers do not encourage them).
Some really seem to come together (mentally) at around that age. Mine did. He was lovely before, but he would stage occasional dramatic performances (read: spectacular blow-ups). He is way more solid now.
As others said, they are a sensitive breed and a varied low-key cross-training work seems to suit them best. Challenge him, but do so in small increments. Always do your best to feel of him to avoid blow-ups. Do not allow anyone else, even a trainer, to “overface” him.
When stressed or rattled, even, if it is because of being “noddy,” diffuse, diffuse, diffuse- relax him rather than make him “work” (that would be an easiest way to get a blow-up). Get him settled and then go back to work.
When spooked or worried, my Morgan, too, relaxes, when I take a firm contact with reins, sit deep, and even wrap my legs around him little tighter. It is little odd, but it seems to help him, when he feels “I am up there, ready to face the danger with him.” He was that way since the beginning.
As for Morgans being a buddy type of horse- I found that to be true with ours and I would recommend to you to find Buck22’s recent post in this thread (post # 7 mainly):
In there, she describes very eloquently the “dangers” of having a buddy horse (in case, your Morgan is one of those- mine is and I could not write it any better than Buck22 did).
It is always walking in a tight spot between still being good friends and being firm enough, so that they don’t quietly take over. The thing is, you have to be friends, because, otherwise, they get sad and sort of offended, but, at the same time, you can’t let them take over, when they slowly bud in and suggest that “taking turns in who is the boss is what friends do for each other.”
Enjoy your Morgan!