Okay, so I love grinding and DLC and constant reclassing/customization for the best results, so gameplay on Normal/Hard passed pretty easily for me. Consequently, I didn't care much for "optimal pairings" or "best children" because I had no difficulty with the stages.
Upon finally starting my lunatic run however, I discovered that this time I wanted to really plan out my pairings, skill inheritance and try to get the "best children in their best classes" possible! I'm absolutely fine with any sort of grinding and reclassing, so please don't hesitate to give me long reclassing paths if it's worth it!
I also have full access to DLC and additional classes such as Dread Fighter and Bride, and skills like Limit Breaker - so there's no problem recommending me pairings that would utilize these skills/classes for their children.
I've done some research of my own, and combined with the pairings that I used in my past playthroughs, I have come up with a draft - please don't hesitate correcting me!
Chrom/Olivia (I've heard that this gives a great Inigo and Lucina)
Inigo/feMU (Chrom or second gen is best for feMU, and Rightful King, so...)
Cherche/Vaike/Frederick (Vaike gives crazy strength and I love a strong Gerome, but others seem to agree that Fred makes a tank Gerome. I'm a little worried about Fred's stats because in my past experiences Fred had quite inferior stats compared to other units further into the game.)
Gaius/Tharja (Noire gets galeforce and that's awesome, but I've always made Gaius the father for Noire...is there any other good candidate for her father?)
Maribelle/Lon'Qu/Henry/Libra (I've always done Lon'Qu for Brady and it worked out fine...but apparently Henry or Libra gives a good sorcerer potential for him. What should I do?)
Miriel/Gregor (My mind is set on this one.)
Nowi/Kellam/Donnel (Kellam gives Nah amazing defense. But why is everyone suggesting Donnel?)
Sully/Donnel (Isn't this the best? I've heard Stahl and Vaike are good, too, but...)
Panne/????? (Seriously, help me.)
Lissa/Ricken/Libra/Henry/Vaike (So much potential...Owain might be a good magic user, but how about Dread Fighter? What should I do about him?)
Cordelia/Lon'Qu/Stahl (That speed with Lon'Qu...but Stahl makes Severa a good hero...BUTBUTBUT)
Sumia/Henry/Gaius/Fred/??? (I have zero ideas. But unfortunately Chrom is definitely out of question.)
Please keep in mind, this is all for optimization and not supports or hair colours...(though I was very adamant on those before...) so no shipping wars!
I greatly appreciate all the input, and thank you!