My main problem comes with the fact that I do not have many units in the Red and Green department. My only Greens at 39-40 are 5*S.Camilla, 4*Frederick, 4*Gunter, 3*Cecilia and 4*Nino. And the only Reds I have at 39-40 are 5*Xander, 5*Caeda, 4*Hana, 4*Palla, 4*Lilina, 4*Henry, 4*Tharja and 4*Chrom. Meanwhile, I have a ton of Lv.40 Blues and Colorless thanks to the Kozaki Event.
The second problem comes with the fact that most of my Lv.40s have either few or no Inherited skills learned. So really, I'm sorta forced to use my Strongest units or just hope I'm lucky with Triangle Advantage.
Anyway, my Main Team is Horse Emblem(2 Hone/2 Fortify), with Fury+Vantage Xander, Brave Axe + Death Blow Frederick, Blarblade Ursula and Priscilla with lots of HP, Rehabilitate and Live to Serve.