Looks fantastic! I envy your screen cover! Mine is too big to cover plus I wouldn't know how to do it even if it wasn't. I'd love to see your pics of the finished work with water features, caves etc.
I'm waiting for the Texas weather to cool off bit more and will be digging up some caves for mine, both for shade retreat and to create hills and mounds that they will for sure love to climb on.
I love uneven terrain for the torts. It creates more sight barriers and opportunities to climb which they love. The only concern is drainage during heavy rains. Enclosed those babies will not be able to escape flood. Lots of things to consider!
Keeping them enclosed is good but we must also consider that in nature they'd be able to get away from many situations by hiding, seeking higher ground, digging into the loose soil, or whatever situation.
When working on my tortoise garden I try to project into any possible scenario that may happen and to counteract it by adding all necessary elements to the enclosure to make it safer do comfortable. For now, my babies go out there for just few hrs every day and we all (family) keep checking on them for any signs of trouble. They have water, food, hides, the garden is very well planted so lots of shade and I have a mister hose that I turn on when they are outI know that I'm in no way ready to move them out there full time yet. They'll have to be much bigger and have longer adjustment period to get really comfortable with their garden.
What I love about your enclosure the most is that it's 100% escape and predator proof! Awesome!!!!! this is mine when I was building it. It looks different now with all the tortoise friendly plants in and others out, the bricks are set and their hollows filled with soil and some plant growing in all those holes of the wall. In a year or two it will look pretty and trailing plants will partly cover the outer side of the brick wall.
I wish I could get a screen cover for top like yours....