Those two are traits he values in all people, what TNE is talking about is err ah, exotic characteristics.
Fetish fuel, basically, which DP pulls from canon since only really out there physical features seemed to really get Viserys interested (he scoffed at a statue of a nude woman, but halted a procession of Dothraki to "examine a statue with multiple sets of teats/other weirdness").
Viserys at one point noted that Azema hits every single note of what he likes, and Siduri pretty much leans to the fucking hilt on those too, just missing the tail or wings. The tail or wings really ties it together.
He would probably also be appreciative of other weird forms of beauty, like skin or scale patterns, etc.
