Your comment inspired me to return to them. Although there's something about the fluff that makes me cringe (that picture doesn't help...), I can see the upside.
I've got some ideas percolating that would recast their fluff; been thinking on the 'created by sorcerer-priests' bit and the caste system in Rhat'matanis, and I think the combination might make them more interesting than the vague 'alien beauty' stuff. But, that's for after working out the pre-existing races.
Speaking of those, went through our 4 non-core races for my final 'sticking point' bullets (the others are earlier in the thread,
here). Here's what I came up with:
* Long-Nose Form, Tengu Wings, and Tengu Raven Form (Tengu feats, pg 166-7): They don't seem overpowered from a crunch perspective, I suppose, but it does seem odd that a non-SLA race has so many SLA feats available. It may work with the LPF fluff, though, where Tengus were originally servants to a god (and thus they might conceivably retain a measure of otherworldly magic?).
* Fiendish Vessel (Tiefling Archetype, pg 171): Probably goes without saying, but since the archetype requires a fiendish patron and exact alignment match, I think it should be out of bounds for PCs under the 'no evil characters' rule. Honestly, even if you could create a neutral fiend as your patron, I think the intent of the archetype is such that I'm not especially comfortable with it for PCs.
* Strongtail (Merfolk Alt trait, pg 195): I think I've heard more than enough good argument against this trait. Losing speed in a little-used movement mode for increasing one you use all the time doesn't really seem like much of a trade-off outside of aquatic campaigns.