Hi
i Find a heat mat is the best option for leopard geckos as they absorb the heat from underneath which a heat bulb would not accomplish.
i also have a 2% uv bulb just to give some daylight to the cage (they do not require this but it makes the vivarium look alot nicer) it has also been reported recently by soldiers touring that they see the occasional gecko basking in the sun. mine like to do this sometimes aswell.
also i would recommend using either repile carpet, slate tiles or just kitchen roll for their flooring atleast until they are bigger as they could ingest any small chip barks or sand which could cause impaction
(which is not good).
i find that my leopard geckos only use the moist hide for sheding if that. i would recommend a minimum of 3 hides. 1 moist (could be placed in the middle of the tank) 1 hot side and 1 cold side. people say they are ground based but i find that mine like to have a good climb and have found them actually sleeping on the plants i have dropping down from the walls.
if you have any questions then give me a buzz

craig