I'm trying to research my way through this. It looks like "initramfs" is for initial booting of the kernal into my computer's ram and "cryptsetup" involves encrypting and decrypting files on my computer as it accesses them. Does that sound about right?
About. cryptsetup-initramfs isn't finding any disks that need it, so it doesn't know what to do. If that's because you don't have any, then following the warning's advice and uninstalling the package should be fine. The warning is harmless in that case though, so if some package you do need depends on it you can just ignore the warning.