What a cutie! He looks very bright and alert, if a bit thin (better than fat however!) I hope he works out to be a great pony for the owner.
I know his feet probably look much better than they did before the trim, but there are some things that can be done that will immediately give this little guy some more relief.
While his heels are still very long all around, his hind heels are actually longer than his toes(!). This is hard to see if you don't know what you're looking for, so I've marked your photo:
• Red dots are where the heels are.
• Blue dots are (very approximately) where the heels should be. It's hard to say without seeing this foot from the bottom and ideally in person.
• Green lines show the length of the heel versus the length of the toe (from hairline).
Here's a website that will help you visualize what a healthy foot looks like: Recognizing a healthy hoof
This page has some EXCELLENT case study photos and information: Treating Founder (Chronic Laminitis) without Horseshoes--Section 20
I would strongly suggest tracking down a barefoot trimmer. I think this pony could be easily rehabbed and brought into riding condition in as little as a year, depending on the rotation present. I hope you'll be able to post xrays for us to see!