HDRI is wonderful. You can also switch on "sky light," which will create a light dome out of the sky preset. Some people don't like this for the somewhat saturated effect it can give. A worthwhile experiment just to switch it on, or load in one of the lighting example presets from the browser. Definitely tweaking the textures is a good thing. Because of the way the texture room is set up it is sometimes effective to create an overall layer that influences all the textures, rather than dialing in each of the hundreds of materials later DAZ figures insist on.