The backyard pump track is a work in progress in its first season. I'm still fine tuning and building, and I just recently scored some dirt and will begin to build it up more. Almost all of what you see here is from digging and moving "lawn", almost nothing "imported" at this point.
Dude, I totally need your help at the park- I was looking at your design here and the one thing I don't know how to incorporate into the park is DRAINAGE!!! You seem to have it well under control for water damage....I will be calling on you for the plumbing of our park!
There are good public pump tracks in both Stowe, VT and Johnson, VT if you get out this way to ride ever. Have you been to Highland in NH? If not, check it out - and I doubt you'll feel that New Hampshire is lacking anything when it comes to riding.