Thank you, and I'm glad you like the site. A lot of work has gone into it (mostly from the incredibly talented site developer), and lots of new and innovative features will be added as time goes by. The chart will be fully up to speed within the next few days, and will then be officially updated as soon as the game launches.
As for using yao guai as mounts, this was a suggested feature under the Wasteland Whisperer perk. It is unclear at this stage if this will be included, but based on the implementation of mounts in Skyrim, as well as the clues in the https://youtu.be/Vw21X2jKwCM?t=52s video (that could well be related to http://hydra-media.cursecdn.com/fallout.gamepedia.com/3/38/Fo3Mrat1.jpg fine creatures from unused FO3 concept art, also shown http://hydra-media.cursecdn.com/fallout.gamepedia.com/7/74/Fo3Mrat2.jpg), we may still end up being pleasantly surprised 