You're amazing, thanks!! Sounds like much more than I thought would be possible so I'm a million times impressed!
I just tried it out and the interface looks perfect, but I noticed that it seemed to be stuck at Unhappy. I did play with the sliders a bit and set them up, but after a stack of meat it still seemed to be an unhappy pet. Then to make sure, I disabled all my other addons and dismissed and called the pet again, tried using and taming a different pet, but it didn't change anything. I haven't had enough time yet to see if the Loyalty is interacting. That always took awhile.
The interface itself is spot on, however, it seems like it isn't realizing I'm tossing food at it.
Edit- Seems to be working today, though the icon for content and happy seem to be missing. Also the loyalty level on my eagle(Bird of Prey) went up to Submissive so it looks like everything might be working properly!
Edit 2- It's been 20 minutes and it shot from Dependable all the way up to Best Friend, even after I turned the slider most of the way down. I thought maybe since I'd tamed the eagle at lvl 25 and was now lvl 35 that it registered all of those levels in between and added it to loyalty (I hadn't used the eagle til now, it's been in the stables the whole time). I abandoned it and tamed a new eagle to see, but this newly tamed eagle is immediately at Best Friend and Happy (also, they don't share the same name). Oddly enough, the Hyena I was originally using up till now (15 lvls or so) is still Rebellious and neither its loyalty nor happiness is changing.
Edit 3- After dismissing, taming a basilisk at my current lvl, and calling the eagle again it no longer says Best Friend/Happy but Rebellious and Unhappy. I fed it, nothing happened, fed it a 2nd time and it went from Unhappy to Content to Happy on one food piece of the same type. I dismissed it to see what would happen if I fed the basilisk, but it seems that before feeding it at all, the basilisk shares the eagles Happiness because it says Happy now.
Edit 4- Eagle went up to Unruly after about 10 minutes of questing, and it hasn't changed yet. So far it looks like it's not going up like crazy as the other eagle was, as it's still Unruly at 30 minutes. Happiness went down to content (from happy) and now won't budge after feeding it a few times. I'm not sure if any of this is helping you out because everything I've given you has been really inconsistent and random. :P