That's a nice looking mali you have there. Have you ever considered putting it on dirt instead of the seeds? I keep most of my reptiles on dirt (my mali uromastyx, my bearded dragon, and my russian tortoise...everyone except my leopard gecko). It is great. It offers a more realistic ground covering, and it is easy to create humid shelters (which uromastyx love, as they typically spend almost all of their lives deep in humid burrows).
For my russian tortoise I have a simple rubbermaid bin (temporary) with about 3-4" of topsoil... I would like to find a better soil, but there aren't any good ones around here, so store-bought topsoil has to do. The important thing about soil is to keep it well saturated with water. Once you get the watering down, the actual enclosure will be low humidity while you can maintain higher humidity shelters for your tortoise. Mine loves to dig a hole and sit down in it underneath hiding spots and other things, because it offers a very humid retreat.
For heating I have a simple 60 watt household bulb in a reflector dome. For low-heat reptiles such as a russian tortoise, I don't like to use flood bulbs or spot bulbs because the beam is usually too tight. I get a nice big even basking spot with this setup that usually stays around 95 degrees f. I have a flourescent UV bulb too, even though I don't really believe they are necessary for most reptiles (because of the little amounts of UV they give off). I figured with a tortoise it would be a good idea though just to make sure I don't get any problems with shell growth.
For furnishings in the cage I have basically two things. On the cool side I have a little hut type thing made out of wood and dowels. He likes to go underneath there and dig, and I put Timothy hay on top of it and around it. On the warm side I have the saucer from a clay pot with part of the edge broken off (with a hammer) that is used as a hide.
This is what I've been doing so far, and even though I've only had the little dude for about a month now, I'm confident that I'm doing things right. You should check out www.russiantortoise.org because they always have great info on russian tortoises, which is what I would recomend for you. They usually stay somewhere around 5-10"
Tortoises are awesome. I'd say my two favorite types of reptiles are tortoises and uromastyx. Bearded dragons don't really interest me. They use a lot of energy which means they live short lives. That's actually why tortoises live long. They are very efficient. I like leopard geckos, but I prefer reptiles that are herbivores, because they are much easier to feed.
So that's about all the input I can give you. Here's a few other species of tortoise you can look at:
Hermann's tortoises (eastern and western)
Star Tortoises...they are beautiful, but usually a lot of money.
I'm pretty sure there are species of greek tortoises too that stay small. Egyptian tortoises too? Just look around. Everytime you find a tortoise you haven't heard of, look it up and see if you can find out how big they get, what they need to survive, etc.