I know this isn't really a "how would you do warriors" topic but I would've done it like this.
Rowan, Lianna, Anna(Bow)
Marth, Caeda, Tiki, Minerva, Draug, Linde/Merric
Chrom, Robin, Lucina, Lissa, Frederick, Virion
Corrin, Azura, Ryoma, Hinoka, Takumi, Xander, Camilla, Leo
Lyn, Celica
10 swords, 4 lances, 4 axes, 3 tomes, 3 bows, 1 dragonstone
I know it still isn't balanced per se, but the series has always had a sword bias so it really can't be helped.