Phineas is fine with me, and I think that puts us in a pretty good place to begin.
We'll have another baby ASAP.
1st girl: Antonia Felicity "Nina"
1st boy: Quentin Malachi
2nd girl and boy: Phineas and Margaret--if you approve
Oh, about the ln. NoC said in the OP that hyphenating the ln for future children is an option, but I'd rather use Russell for the kids than Gilmore-Russell. It feels a little...not right to use "my" late husband's ln for children that aren't his. I would like, though, for Alma to use Gilmore-Russell for herself so she has a tie to her older children's ln. WDYT?
If you agree, we're probably finished unless you want to hammer out the middles for Phineas and Margaret right now or come up with our third child picks.