It seems like she'd be better off with someone like Pavise Armsthrift Galeforce Luna Limit Breaker.
Why would she need Vantage?
Sorcerer's are best reserved for the enemy phase. Galeforce is only useful during the player phase. You want Vantage so that you're guaranteed, when you need it, the first hit to start draining some health with AN. Pavise and Aegis can alleviated the need for this by making it virtually impossible for your unit to ever reach <50% HP.
Counter will be the only non-RNG weakness of either build.
I think Donnel is a great father for Noire. Although his stat mods aren't perfect, at least they do not hurt Noire in the long run. It also gives her access to Gale Force, Armsthrift, Sol, Counter, and Renewal. That allows her to have some pretty interesting things OUTSIDE of being a Sorcerer. I also enjoy the hair color he gives her.
Lastly, I kind of dislike using Donnel otherwise. At least it's very hard to hurt Noire, and when in doubt - make her a Sorcerer. So it kind of keeps Donnel away from hurting the other possible children he can father. Especially since some of the kids need to have high stats for one stat or another since the other children need to fall into a certain role for maximum performance. Noire just goes "I'll pick up this random weapon and MURDER EVERYONE."
Aaaaaaaand yes, I know Galeforce can kind of be over-rated. However, for the likes of Lunatic+, it allows me to have some breathing room if I have many units who can get an additional turn. Same goes for Lunatic. That's another reason why I would pick Donnel over Gregor (usually better for other children anyway) or Stahl (great for other children too).
I recommend Owain. He always seems to get fathered by MU. Ricken is good with him, but I'm not a fan of the Sage overlap on that pairing. And Sorcerer fanatics seem to go Libra, but that's whatever. So yeah, I wanna see what else is out there, as I'm considering Stahl!Owain.