Haha I know quite a few people who are much quicker uphill than down, easier on the quads.

At a 6:40 pace I’d be suggesting just to shorten your stride a little, almost feels like skipping along the top of the ground a bit and keep it up, it’s hard to do it at the start. And really just focus on doing more distance but slower. Aim to do 80% of your weekly mileage at a heart rate between 115-140 and see how your body feels.