I've often thought about going for a run there, but it's never worked out. There's a parking lot a few hundred meters east of where you were at 5.7 km, that's where we park to fly hang gliders. But when I'm there it's always winter and I'm dressed pretty warmly. The terrain looks very cool, looking forward to your opinion.
There's some fun mountain biking in there if you know the trails. Lots of blueberries! Bash bash bash.
The trails are nice, worth running there. The topography is, as you note, really neat and the vegetation ranges from not bad in the west to terrible closest to the ocean. The not-bad stuff seems like mostly blueberry bushes under pitch pine. The bushes are at best shin height and at worst waist height, but I didn't notice anything tangly or sharp, so it would be kind of Norwegian-style running—more work but not a fight. The terrible stuff seems like a lot of scrub oak and I did not try running through any of it. The bottoms of the depressions are a lot more likely to be notFun.
What I've been into the edge of was probably worst of it, right near the parking lot. I haven't been there in like 3 1/2 years. Maybe this winter.