Or you can just do what i do and let freddie draw an archer out in random battles, box them in and then let Donnel go to town on his trapped little behind.
Once he reaches level 15, Mercenary it goes and watch his stats skyrocket from utterly pitiful to godawfully high. Seriously, he gets like 6 more speed and 7 more skill. And he has swords! He can actually wreck brigands now!
The official Ardha of the SMT IV board. So much sodium against the WiiU!