Congrats on deciding to join the happy family of Uro owners! 
Your setup shows that you have done your research which is phenomenal, and happens much too rarely The only thing I would say is to be careful with the bricks. I am a chicken and have not used any sort of materials like bricks, but there have been discussions about situations where the Uros have gotten lead poisoning or had other adverse reactions to building materials like that. With that said though, people do seem to use them... so hopefully others will weigh in on that.
I had a decent siezed adult mali in a 40 gallon for most of his life and he was happy, so that should work for you for quite a while. As the little guy gets bigger, the thought of "more space is better" comes into play, but I think the general consensus is that the 40 gallon breeders are the smallest acceptable size for permanent Mali housing.
Adding something taller for the Uro to climb on and get within 10-12 inches of the UVB strip is probably a good idea. Though if they are like my two at all, you will have to develop a thick skin to the hollow thump of them "jumping" from the top (looks like falling to ME...)
Uros in general are diggers and like to dig, even if they can't get very far. Substrate is always a complicated topic though, and much debate surrounds it. The three *mainly* used setups around here seem to be sand (washed playsand, not calci-sand), birdseed, or dirt. I personally use playsand and have had good experiences with it, but there are pros and cons to all of them. Depending on how old the uro you are getting is, the shelf liner may or may not add a little stress to their lives. I always recommend (and generaly the forum agrees), to keep juvies on paper towels, or something similar, until they are about a year old, and then switch them to a digable substrate. If you are getting an adult, I would urge you to take a very close look at the substrate options before deciding on a non-diggable option.
I can probably count the times I have offered water to my Uros on both hands (just straight up I mean), but they have never drunk any, I know some uros do though, so just watch the humidity levels and that should be fine.
Your diet sounds great, off the top of my head I cannot remember if my multivitamin has D3 in it or not, but I know many people DO supplement with it, and sadly I made the choice so long ago I can't remember. (I use the herptivite calcium and multi) For treats, things like hibiscus flowers (but not from the store, etc), peas, etc can be fed. Archie (my adult) used to do almost anything for grannie smith apple pieces. Mosca, my juvie, could care less about those but LOVES sugar snap pea pods. Finding out what foods they will flip for can be very helpful while interacting with them.
I do not feed seed regularly, but from what seems to be posted is that just about any see can be fed as long as their are no sunflower seeds in the mix. It is not the seed itself that is the problem, but the shells can cause some serious problems.
Beans should be fed raw, though I have no idea what would happen if they were cooked. To my knowledge noone has asked before, lol. For juvies, the beans should be ground up, some people even dust their greens with the powder. For adults, you can leave them in bigger pieces. Mine seemed to get great enjoyment out of crunching on them.
Humid hides, lol. Some people use them, some people don't. I don't, but my Uros ALWAYS have some part of them shedding and almost never look as cleanly shed as many of the pictures in the forum. So, I would say this is another point where hopefully people will speak up.
Congrats again, and welcome! Keep us posted and keep asking questions!
Elizabeth
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1.0 Mali Uro Archimedes (May he rest in peace)
0.0.1 Egyptian Uro Zuberi Mosca Khu (Mosca)
0.0 Fish
0.1 Sulcata Minnie
1.1 Iguanas Flik and Loki
0.1 Newfoundland Jasmine (RIP)
0.1 Feline Winter
Indiana & Wisconsin
