Which marriages would be most optimal if lesbian and gay marriages were in FE:A, and everyone was bisexual? They get their kids from adoption (ex. Brady was adopted from Libra's orphanage or something).
I'll start: Cordelia x Sully:
Kjelle gets Galeforce, mercenary tree, and dark mage tree (all breakers, armsthrift, sol, galeforce, and luna... what else could you ask for?) Severa gets all breakers, luna, and vantage.
Olivia x Tharja is pretty popular. How about Chrom x Gaius? For storyline purposes, Lucina's mom is still the Maiden as the surrogate. Besides, Gaius is often given to Tharja whose with one of Chrom's best wives.
Sully x Cordelia would unfortunately remove the lesbian implications from Kjelle. Gaius can give her a male only skill too.
Donnel may have to go to Nowi though if you decide to give Gaius to her instead
Burroughs: Scanning...Excuses, unjustified resentment, self-justification, a rash desire to negate oneself...I don't see any good reason to join their cause.