One change I made the last 20 weeks to my leg training , I stiff leg deadlifted twice a week every week. I stopped conventional deads as my back thickness wasn't improving from them anymore ( that was a personal thing as I feel I have near maxed out my deadlift , that's the only lift I have done that with ) , so Tuesday's main leg session saw 2 sets of high rep sldl work with dumbells towards the end of the session, best I managed was the 80s for 20 reps. This induced a panic attack with breathing every time but It got done. I always did a curl before and after the ham work, again both were in 15-20 range as this was light hams after my heavy quad work.
On a Friday night , after having done arms in the am. I did heavy hams. Always started with a heavy curl rest paused 8-4-2 into forced rep them eccentric failure , something brutal. Then it was two heavy sets of barbell sldl. I got these to 280kg x 6 and then a back off set of 220 x 12
Then another rest pause Ham curl variation.
I did these every week for 20 weeks , beat my lifts all the way through , and then once got the fat off they are what was left so was super happy.
Moving forward I will aim to beat my heavy sldl , 300 x 8 is my target.
And then I want to master a sldl muscle round, I feel a cluster set is now a great
Approach to added hypertrophy as I feel I have maxed my high rep sets , I just can't beat
The 80kg db for 20 reps , so I need a way of growing in my second session of the week that isn't just more heavy work. So a cluster set is that, 6 sets of 4 reps , 10 seconds rest between.
I will flop flop each week between db and barbell, looking to drive both the heavy numbers up and muscle round numbers up. And then we shall see the potential gains that will bring

Try doing that for 4-5 months and see what happens to ur hams. It's impossible for them not to get a lot better , it will make you panic breath though and fear for your life haha , so be warned