Rules of thumbs for amount of rock vary. Most people say 1.5 lbs of LR per gallon of tank, though when you add LS to your substrate, you can reduce the amount of rock. Of course, the more rock, the better, as it harbors all the good bacteria & micro/meso fauna (pods, worms, other critters). At some point, excessive rock displaces your water and you have no more room for fish (or water circulation :lol: )
I go lighter, but I'm also planning for a smaller bioload (fewer fish).
If you're concerned about digging critters, you can put PVC or eggcrate foundations in your tank before putting in the substrate, then, put in the LS, then, place your rocks on top of your foundation. I defy a digging critter to dig through a 4" PVC fitting
If you go with the TBS package, you can go with their recommendation for your size tank, or you can downsize about 20% (say a 60g package for a 75g tank). No 'curing' needed, just a very quick nitrogen cycle (on the order of two weeks). They recommend 2 lbs/gal, because the native rock they use is denser. PM me if you want more details.