Looks pretty good, is this your 'first' render?
Easiest is to either amp up the Render Quality setting to your liking, or disable it and set Max Time to 0 (infinity) so Daz keeps rendering until it reaches your given Max Iterations, which you can stop anytime you're satisfied.
Otherwise if you mean tips on setting up your scene, lighting is indeed the key so keep at it. A few other things:
-HDRIs are a nice and ready option to play with for a 'realistic' looking scene. You can also experiment with prefab light sets
-Use HD assets for your characters when you can to get the most out of them
Hope that helps.