The very best comprehensive care sheet is from Deer Fern farms. It addresses everything from species, size, food, caging, vitamins, heat, uva/uvb, breeding, etc. Every person on this forum will have a slightly different method or opinion as to how to best keep their uros. If you read a lot of care sheets and the advice is fairly consistent, stick with it. I will give my opinions on your questions, and that's just what they are...my opinions and what I may do and what has worked for my animals.
Substrate: Very debatable. Some use washed playsand, some use deep dirt and some use millet bird seed or sifted wild bird seed. Each has its' merits.
Food: I feed daily. Turnip, mustard, dandelion, thawed frozen mixed veggies, sweet potatoe, squash, dandelion flowers, hibiscus, and on very few occasions, kale, spring mix, red leaf lettuce, tiny bit of fruit, collard greens and many other things.
I also have a "dry" bean mix available at all times.
Supplements: Repcal calcium, herptivite and Uro dust I make a big batch of food and use the calcium/herptivite twice a week and the uro dust every time. I use this sparingly.
Setup: Cool side, caves, logs, cork bark. Warm side, slate, retes stack.
Handling: Individual preference. Handling is easier with cb than wc. Patience is the key.
Basking/ambients: Basking around 110-120, ambients high nineties to 100, cool size in the 80s.
Hiding: Most cb are out all the time. Wc take a lot of time to be out when people are around.
Size: One of the smallest, around 10" is the Somali. One of the largest, can be 2-3' depending on subspecies is the Egyptian.
Lots in between. Malis and Geyri are very popular.
Best Species: In my collection, the ornates are the most friendly, happy to jump right on to your arm and sit on my shoulder. These are my pet shop reptile ambassadors. Each species varies as does each individual animal.
I have had uros for three years now and mine are all doing well and very healthy. Good luck, uros are great.
Pam 
