I have a Welsh D that sounds very similar to Paddy, when he's good, he's a fantastic performer but once he gets uptight it takes weeks for him to settle down and in the meantime he is, quite frankly, dangerous.
I am under no illusion that there are are riders/handlers out there who could handle and bring out his talent (unlike me due to the damage to my confidence over the years) but to be quite honest those talented, confident, experienced horsepeople have their choice of good horses especially as things are now so why would they want my fruitloop? The real danger as I've found out the hard way is that so many potential buyers and loaners have a far higher opinion of their skills than are justified and are putting themselves and others in real danger and stressing an already upset horse as they learn their limitations.
I retired mine at 14yo but I'm very aware that if my circumstances change he would have to be PTS as I cannot risk him ending up in the wrong hands - put it this way, when the news of Spindles Farm came out one of the things that occurred to me was that it would have been so easy for mine to have ended up there if he was passed on.
Obviously i have never met you nor Paddy, however the more i read.. the more i think he needs routine and would probably thrive from being worked every day. He really does look like a cracking little jumping pony and i think he'd be an asset to any PC/RC/School/Uni team. I def think the idea of loaning him out to a equestrian college would do him the world of good. You never know, you might even find that a student falls in love with him and wants to buy him/loan him themself! But i also agree with the people that say you should check out the EC's carefully and ensure that all his needs are going to be met, and that your happy to leave him in their care.
Paddington sounds like a great pony! His behaviour is certainly no worse than what my 14.1 jumping pony did. In fact if anything, he is much better behaved What I'm trying to say is, he sounds perfect for a confident teenager who has regular lessons and gets out and about a lot. Don't be put off if they haven't had experience of tricky horses yet - it doesn't mean they can't handle them.
Good luck. He sounds like a great little horse and I hope you find a good home for him.