Db...there is something beautiful under the poison ivy and fox grape. That rock is amazing.
You can do something even more beautiful once the rock is exposed and you/we can see it better.
I have 2 concerns with what you have told us.
Deer love sempervivum.
Roundup is best at killing grass (and humans ..It just takes much longer).
If you must use chemical poison, you need a brush killer for poison ivy and fox grape.
Cross Bow would be much more effective than Roundup.
Goats would be the most effective. They would leave you some fertilizer and no chemical residue.
I think I see Vinca at the bottom of the photos. This would bloom with some more sunlight. I think I also see the (5 part) leaves of Virginia Creeper, which if it had enough sun would give you very red foliage in the fall. (Roundup will not get rid of either of these).
