Many times, I started going up there when there were only two breweries. I usually walk round the north reservoir and cut off at the top which brings you out near Hackney and Wild Card. Then walk down from there.
I'm not a fan of Signature, although most seem to be, but there are plenty to go at.
Anyone done the Blackhorse beer mile in/near Walthamstow?
https://www.blackhorsebeermile.co.uk/