Totally agree on this. The whole High Elf topic proves that devs are listening rather to the claims that say "give us" then to those of "don't give them". I also think it is pretty likely that blood elves will get san'layn options too, it is long standing request and many players would love to have this option, not to mention that it lines up with SL thematics pretty well. What I meant is that I could easily live without dark and tanned skin tones on void elves, but you are right that we can't stop them going live. Those tones are not vital for high elf fantasy and it also don't really contribute to the void fantasy either, on the other hand, you can see it as a way of "sun elf" aestetics, which can make blood elf fans feel unique. As for me, I can easily ignore those skin tones once they are available in the barber shop since they does not really align with my image of elves in warcraft, but I guess it's good to have these options for people who cares and likes that.
Truth is that blood elves are quite short on new customizations, compared to other races. Maybe they will not get much more at the launch, but devs clearly said they will continue to add new customizations during course of expansion, so I'm confident blood elves will get more stuff in later patches. It is also likely that when void elves get new customizations, blood elves will inherit those as well, since their models are identical and it likely take little effort to recolour new assets and transfer them to blood elf.