Dang son, level grinding is a must then. Don't let your team mates get destroyed. (I personally restart almost everytime I loose a soldier.)
Keep in mind, unless you have a mediator, you'll not be able to get new soldiers for awhile, and I don't quite think you're pro enough for a solo Ramza challenge. xD (But don't feel bad, my solo archer challenge ended right before chapter one ended.)
I don't recomend just getting recuits from the soldier office, they will all be pathetically weak. :/