Well, I don't think the list of official yuri couples in shows like these is long enough for you to have many examples to draw from.
I'm just talking about bait characters. Reina and Makina are specifically stated to have a sibling like relationship, though that won't stop anyone from jumping to conclusions.
Such characters are there to draw in certain otaku so killing them off is counter productive. Take a show like Strain which killed off lots of people but left the two lesbians alone.
... Calling Macross 'darker and edgier,' even relatively speaking, is a silly notion anyways.
yer right on the listing part. after a little jogging of my brain, here's what i got.(i got the series with any kind of mecha action.) and even then only one is a canon couple.
Kannazuki no Miko, Iczer-1. Shattered Angels, Rinne no Lagrange, Idolmaster Xenoglossia. stretching things a bit, M Frontier.
The first 2 are the only series that where something bad happened to the couple.
although, i wouldn't really mind seeing an actual lesbian couple in this macross. COME ON KAWAMORI!!! the increased usage of idol tropes has already increased the possibility...and now i'm sounding like Generation 1 Perceptor.
on a side note about S.T.R.A.I.N-who are those characters? been a really long while since i watched this show which also happens to be a personal fave of mine. oh the irony. XD