I started doing those Bulgarian split squats more. I like that you can adjust the angle/direction to target different muscles. I both love them and hate them at the same time.Single leg exercises seem to be a bit better for my back also. Can still get a challenging weight but not much load on the spine.
Without weights the front foot still gets a decent load. Grab a couple of 80s and you'll know something is happening. With Bulgarian the lean forward or back hits the quads vs glutes more.
It's a bastard of an exercise