I dont know if I am the only one who does that. But every game I start I usually look for weaker groups of bandits and solo them with my character, its AMAZING exp and money just for yourself, I usually solo those groups up to level 5-6. But you need to be careful, only do that if you have TOTAL control of the mounted combat tricks, like slashing enemies in the neck when they open the guard, so you can deal as much damage as possible.
If you get captured dont worry, they will carry you around you will escape with 100% health (hopefully with your itens too) then you kill the rest of them and get your money and more back.
If you manage to solo like 2 groups you should be able to have money to recruit mounted mercenaries, they simply destroy all kinds of bandits and riots, your party will be just walking thru them having fun, after that you keep getting mercenaries (make sure to not go over 30 or so in your party, so you can out run the bandits easily), keep hunting them down, you can do that until level 20, after that you are good to start the massive fights.
Personally I do that even after level 20, its really good money with looting skills high, you get alot of armors that you sell for 400-500 each, plus you dont lose any honor or popularity with villages looting them, and get alot of renown.
I hope that helps you.