It won't be that bad for you. Trust me, you have everything you'll need (outside of a cavalier/Paladin)
Just throw more time into Priscilla than Serra. You have Lucius for Light magic, Priscilla for staves/anima.
Eliwood - 50/50 lord. If you get blessed, great. If you get screwed, good luck
Rebecca - Most underrated character imo. Easily able to handle fliers, also handles archers and more importantly the magic users.
Bartre - Awesome poor man's transporter. Throw him the boots and some con. You get a tank who runs over everything in his way while keeping a frailer Eliwood safe
Hector - He's Hector. Either an axe-using Oswin or a monster
Serra - 50/50 healer, depending on how the growths turn out. I've seen junk, I've seen beasts
Matthew - Solid utility, all you need him for. Can fight too.
Priscilla - The MVP of this run. A poor man's Pent, but has a horse. Feed her all of the staff exp.
Lyn - A poor man's Guy. Frail, fast, can hit hard
Florina - Amazing unit, just gonna be frail. She gets the priority in LHM
Raven - He's Raven, can be junk or can be a monster
Lucius - Frail but worth it. I had him facetank Jasmine to death once so I could buy turns for exp for a bonus chapter
Ninils - Refresher. 'nuff said.
Hawkeye - Solid character. Can tank and hit hard, good to climb mountains but will be overshadowed by Bartre and Florina
Karel - Not worth the turns. If you get him by accident, good.
Nino - Eh, can be great if you give her all the sidequest exp
Jaffar - Monster of a fighter with Killing Edges. I had him assassinate Lloyd to death once in the final chapter.