I’m not far from you so Epping is my local ride too. I have been buidling up a picture of the more interesting (blue) trails on trailforks recently, some even have jumps! Sadly most of the runs are quite short and interspersed with smooth boring fireroad but its worth having a good look around, I can still use 150mm of sus on a handful of trails if you go at them hard.
http://www.trailforks.com/region/epping-forest/
I haven’t been to Broxbourne yet as I hear there is some issues with a private company blocking off the good stuff. Woudn’t mind being shown around though.