@iroro1 I definitely had ankle mobility limitations! Just stretched the calves a lot and spent time at the bottom of a squat when working on mobility.
I think a big part of my reps shooting up quickly is due to my lack of previous leg training (I had a lot of room for growth).
Pistol squats were always my first leg excercise on leg day. I started with assisted pistols as well. I think always getting all your reps in is huge (dropping weight/difficulty to finish a set).
Doing slow negatives, pistols on a raised plane, using trx for assistance we're all things I would do once I couldn't perform my proper reps.
My biggest suggestion is get 4 sets of at least 5 reps of anything. Track that progress week to week adding on one rep of something more difficult in those sets.
I also have done a lot of slack lining in the past few months and I basically would do a high step up every time I got on that dang thing so I'm sure that helped a lot.
Good luck on your journey!