I’m pretty sure I didn’t mess with systemd, though that would probably be the right way to handle it.
I was able to update a runtime config so if any storage wasn’t available it just halted the service. Then I created a short script I’d invoke manually which decrypted the luks drives and brought the dependent services up. I also added monitoring to alert me when the drives weren’t available for whatever reason.
Tmux with a few custom key bindings is amazing. Kind of a learning curve, but not nearly as difficult as something like Vim.