So it essentially is just you have no reason to use Cav's over Fliers and 1-2 range units, and the cav line is basically the 1st tier skills is all you want?
Im guessing you want to get Silas into WL to compliment his growths and keep his lance rank
Jakob (1) marry Dragon Talent Corn for Malig and stay Malig for bolt axe, or go WL for better physical stats
Peri into Mechanist (marry kaze) for ok mov, 1-2 range, and abusing her personal + Replicate late game (if you save the c13 arms scroll for her) or BowKnight(A+ Selena) or get her into Kinshi (Im not sure how, maybe A+ Mozu if she can?)
Xander can stay pally since he has 1-2 range
This seem about right for all the natural Cavaliers? (Well and Jakob but Jakob (1) is essentially a natural paladin anyways if you use him right)