Help on Soul Shields

I recently started farming purple BSH soul shields, and I got a few to use. Following this guide https://docs.google.com/spreadsheets/d/1jR1hRSRS4q-uGLisKavViVRb2E8lmz2sR5AzzFPYj9U/edit#gid=1033264247 I decided to go 3-7BSH and 1 2 8 Mushin. But after looking at the guide again and unsealing my shields, I noticed that some of the stats don't match. My BSH #4, for example, didn't have any base Crit, while on the guide it says that it should. Do soul shield drops have random combinations of base stats? Also, what do you guys normally do when enhancing your shields? I've been using Elite Crits from dungeon drops/EFleet/NSH, but I noticed that the crit values vary depending on the Elite Critical stats. What's the max additional value that you can get for enhancing?

Thanks :D

Edit: Also I'm a KFM if that helps. And suggestions would also be appreciated