It depends on what type of character you have in mind. If you want the heavy cavalry or sword and board type of character, your going to have a tough go at it early on. You will have no choice but to avoid many battles until you get enough levels under your belt or proper troops to sort them out.
However if you build a horse archer character, you can butcher elite troops with the exception of ivory archers early on. Fight a few battles against scarred bandits, with nothing but bow and arrows. Invest your skills into Horse Archery, Power Draw, Looting and Riding. 4 or 5 is the sweet spot; this is very easy to accomplish hunting bandits near Suno and Uxhaul.
Kill bandits with arrows all by your lonesome until you've amassed a respectable amount of wealth to purchase a good horse, bow and arrows (5k-8k) Leave off from buying armor and melee weapons for now. Once you've got a good charger and bow, go hunt down Holy Crusaders and make sure you face them on rather even, open terrain. Ride circles around them and shoot their horses out from under them until they're all unmounted. Do not get in a flat our race with them chasing you, just circle strafe so they won't catch you. Pot shot any in the face who open up to swing, otherwise just shoot horses.
Once they're on the ground, trot your horse while they get near to attack you, and shoot them in the head. Once they're dead, you get your big fat renown boost, a nice loot to boot plus 422 exp per kill. You'll be inundated with swadian full plate armor, gauntlets, iron boots, great helms, knight helms, knight maces, and knightly chargers. Rinse and repeat as necessary. By day 30 I think I was level 27 with a posse of 10 swadian paladins and kitted out in sturdy swadian full plate. Once your strong enough to can alternate to using those nice knight maces they carry to knocking them out, and taking them prisoner to recruit to your ever growing elite posse.
Basically any unit without a ranged attack is a sitting duck, use it to your advantage. Granted I've played this game a while, and have it down to a science, but once you learn how, its really very easy.