I agree that their should be money earned for a kill, to force even peasants to try to kill someone in the back or such. The gold reward should be scaled trough your level, like if you're lvl 1 to 10, you get 50 gold per kill, as we all know it's fearly impossible to kill when you got a wooden stick. From lvl 10 to 20, you may get like 20 gold, and as you get over lvl 20, you receive 5 gold.
Or another possibility -but i guess it would be hard to set up-, you gain more or less money due to the lvl you have and the lvl of the opponent you just killed. A lvl 1 killing a lvl 30 wins like 50 gold, and the other way around the lvl 30 wins around 2-3 gold.
To conclude, i'd say xp gain or gold after a kill would be great to force everyone to jump into battle like we used to do before the patch, to get some more money.