After compiling more and more rigs because of how fun it is. I finally decided that 1200 rigs was WAY too many. A lot of the factory rigs just weren't getting used and a lot of the rigs I downloaded either weren't great or had multiple versions of the same amp going. My Kemper was taking well over a minute to boot so I started the purge.
The way I did it (not sure if there was a better way) was as follows:
Cleared my UBS shared folder
exported all rigs to USB
Deleted all Rigs from Kemper quickly hitting "Delete" and "YES" one after another (took about 5 minutes)
opened shared folder on PC and cleared off all Rigs I knew I wasn't using. got it down to about 300
Went through and listened and checked the remaining rigs and deleted about 100 more
Cleared my UBS shared folder Again
exported all rigs to USB Again
Backup Kemper
From now on when I test downloaded rigs I will delete them immediately if I don't want to keep them
Kemper Boots really quickly now