Spotted...

I used to climb that escarpment once a day as well during the couple of years I worked up there. Could really grimp back then. Just a distant (muscle memory) now.

What I'm saying is, I used to be a climber like you.

You clearly need to keep working on your power to weight ratio to get the mythical output figures I achieve. At least you have youth on your side you bloody youngster. I better not continue for fear of being reported for grooming.

Highgate on the other hand is tricky with crampons and ice-axes.

Try Nordic walking poles and roller boots, much easier.

Kingsland road is a steep enough gradient for me these days (northbound).

Only solution for you is an e-bike. Sorry but some are too far gone for my sage advice to have any effect.