I struggle with aquascaping sometimes too, the rock selection these days i find is pretty weak. It's all mined stuff and no nice shapes like you could get 20 years ago. Other times its a total mixed bag from all different parts of the world, making it just not look right together.
I did a rock pile a few times, they eventually start to shift around. they slump after you stack em and become mounds. They also highlight the mismatched rock.
I would do the following to help get some ideas flowing:
1)Group similar styles or shapes together, like Tonga branches, or Filji boulder or whatever you've got there, maybe put all the mined and obviously man made rock into its own pile.
2)try to visualize how you want those individual piles to look. What pieces look best together. Maybe you see some of them making some shelves, and another forming an arch, maybe some of it is totally base rock and not to be used in the main structure.
3)Find your heavy slabs and use them for bases. If its ugly, bury it!
-you can drill small holes through really dense rock with a concrete drill bit pretty easily.
-Slide an acrylic rod through the hole to give you a place to skewer another rock. You can form effective arches and pillars this way without glue!
-If you find a form you really love and don't want it to move around, then get some of that reef concrete stuff, there's all kinds, reefcrest is what i use right now. It loks really fake, but it has great holding power, and its so fool proof to use, if you mess it up, just put it in hot water and it goes back to being flexible again.
4)You don't HAVE to use all your rock. If you make a nice form and there's lots of exposure around it and its really porous rock then you don't necessarily NEED all of it, don't crowd your tank because you feel like you have to use it all.
5)If you feel like you are wasting some of your rock put it in a bucket, and store it, or break it down and put it in your sump for added filtration if you really want to. But hold onto it because you'll likely upgrade or expand one day. This doesn't apply as much to man made rock, but definitely applies for any real imported rock. The shapes you get nowadays are seldom any good compared to the old stuff, so if you've got old school rock its good to keep it.
Too bad about this COVID thing, Aquascaping can be really fun, Like Lego for grown ups. lol
Try having a couple puffs of some sativa, might get those creative juices flowing too
Cheers!-Ken