Right ill do this in bullet point form
1. Hot side has alot of discussion on what temp it should be at, personally I have mine at 86-88 ish on the hot side. the cool side should be around 72ish.
2. Leos require belly heat, so hook your UTH to a thermostat and this will regulate the temperature for you. (i suggest pulse proportional)
3. Im for UTH all the way, belly heat is most important, you will find your gecko may spend most of its time in the hide anyway you wont know untill you get your gecko.
4.Regulating the temps again with the use of a thermostat hooked up to your UTH. (UTH covering 1/3 to 1/2 of the floor space.
5. You can have a thermometer for the hot and cool side, I only have one for my hot side. (I can move the probe to check if you get a digital thermometer you might get a High/low function with it so you can check and adjust for any fluctuations)
6. I believe people use eco earth in some of their enclosures, Others use shelf lining, Slate and tiles. It is up to you but I would say that is the safest things to go with.
7. No sand in the tank what so ever. No compromise.
8. yes you can buy them at pet stores or make your own, each will work well, a variety of people make them on here out of tupper ware containers because they have so many geckos and its just easier.
(I use sphagnum moss for my moist hides it doesn't really matter aslong as they hold moisture well)
9. If you have a problem with storing feeders, a great staple diet for leos are mealworms, you can store in fridge for like 3 months if needed, They don't stink and you just have to chuck some apples/oranges etc in there for moisture and gutloading.
Other feeders I would suggest is Locusts as they provide a higher protein package then crickets, plus they don't stink to high heaven like crickets.
10. I use JBL micro-calcium without d3 in a bottlecap inside the vivs so they can lick it when needed.
I dust with arkvits (this has the vitamins) once or twice a week,
As for the gutload for crickets i don't feed gutload so I wouldn't know.
Hope this has helped.