I've just checked your welfare range table and it's a pretty amazing work you did there and the illustration is gorgeous :)
I'm a French science populariser and I'm mostly specialised into farm animals and fishes.Here are a few thoughts I had when reading here and there, especially the Excel file, if ever they could be of any use to you :)
Maybe adding sheep might be a good idea as most of the studies on the appraisal theories framework have been done on them and that could add a few things. Veissier and Boissy's work and Lucile Greiveldinger thesis have very interesting things.
The last part of her thesis has a non-published study (but I have it, if you need it) of the influence of the social rank in the expression of the emotions in sheep and actually I'm quite sure I have that also in at least one fish specie, if ever you could be interested.
Sheep is also the specie with one of the most impressive known self-medication abilities we have today.
On hen we also have the "higher" level of empathy, cognitive empathy. In your references is listed the "lower level one", it might be worth adding this paper which is much more exceptional : https://doi.org/10.1016/j.anbehav.2013.05.004
I see a "Trace conditioning and pain", I'm not really sure why both are linked as trace conditioning itself is often given as an interesting cue to study consciousness, if it's mostly trace conditioning that is of interest to you, then here is trace conditioning in a protocol on chicken http://dx.doi.org/10.1016/j.physbeh.2014.05.023 , also herehttp://dx.doi.org/10.1016/j.anbehav.2017.05.025 and it's used in the protocol for pigs here : https://academic.oup.com/jas/article-abstract/92/11/4878/4703585
You might also want to add trout or make a salmonid (as you already have an "octopus" or "bee" case for several species) because we have studies on trace conditioning as well there https://link.springer.com/article/10.1007/s10071-009-0267-3 (as far as I know, we have shows trace conditioning in a few other species like cod, and as salmon and trout are pretty close and we have a few other very interesting stuff on trouts... ^^)
Play in bee now has an actual reference since last week ^^ : https://www.sciencedirect.com/science/article/pii/S0003347222002366
I've noticed in the references table that you often have only one paper, I don't know if it's done on purpose but there are often much more to backup your position (for example in bee judgement bias, there's a pessimist but also an optimist bias paper https://www.science.org/doi/10.1126/science.aaf4454 )
I'm looking forward to see where all this goes ! Far, I hope! Nice job :)