never use ambient lights... full stop

for sunlight a directional light is best but you may end up with very hard shadows(this maybe the effect you want). experiment.

For the candle you should probably be using a combination of spots and points. Start with one light see how it looks, add another see how it looks, add another etc etc, that's how it works. Remember that real life light bounces and CG light doesn't. You need to always be thinking about bounce light and how it can fill in the darker areas (you shouldn't really ever have something that is jet black). Keep trying and keep experimenting, do you inial lighting on a sphere rather than your model as the turnaround will be quicker and just as useful.

that's enough to get you started.

keep trying all the time!!


A

Ps. NO ambient lights!!! (for the exact reason you said, they make things flat, the reason being that they pass through every object and apply light evenly to the object hend why it's flat. Make sure you use your shadows effectively and make sure you turn shadow casting on!)