Pulled 2 Hardins & need your suggestion!

I'd keep the +spd - def. With a Atk bane harden goes starts dealing 47 damage per hit which isn't something you want from an armored unit, especially on initiation (due to bold fighter allowing him to double) or if you're using him as your magic check because he wont secure KO's. Having 33 Def doesn't hurt him much since brazen Def/Res patches that up, or you can give him Steady/Warding breath depending on which one you use more.

I'd give Zelgius your spare Bold Fighter because he is by far the best user of it with his Black Luna. Once you give Zelgius a Breath skill in his A slot he'll be able to ORKO 90% of the units in the game with it.