I agree, all the 3 mentioned above. I mostly adore Santae. I could also use some referrals, maybe here I'll find a bit of help with that? Santae
 
If eye popping is the context here, I don't think any virtual pet game beats Kinectimals on Xbox 360 then. The animal rendering was simply incredible. The way the animals behaved and even moved was the realest that I have seen after playing virtual pet games for more than a decade.
 
Honestly, I'd go with Santae, Subeta, Lioden, Flight Rising and Aywas. They all have some quality graphics, however, Powerpets, Runetails, Atrocity and Marapets along with Neopets are loaded with features & gameplay elements.

Webkinz is also up there in terms of features. Umbra pets' graphics also puts them in align with quality graphics. The graphics on My dream pony are also great. Pawborough and Mythaura's graphics are pretty nice as well. Mythaura will be released sometime next year, but pawborough is currently in beta testing.

Even though, Evarenity is currently in development, I like their art too. It'll be interesting to see the game in action once its released.
 
For me, I think the following stands out to me the most
1). Subeta,
2). Santae
3). Flight Rising