I checked out your video collection. You have some very interesting stuff and I think I may be able learn a few things.
I also live in Texas, north Texas, on a dry limestone outcrop with soil depths averaging about 6" but highly variable due to the sloping nature of the property. My best, most fertile soils are underneath the hackberry/cedar elm/live oak stands on the property where leaves are allowed to accumulate and decompose. In the cleared area, it was farmed for hay, beans, corn, etc before we bought the place, the soil is pretty light, tends to dry out quickly and can be difficult to dig if it hasn't rained in a while. Under the trees it is dark and richly connected and you can dig with your fingers to the rock ledge underneath. It's some good shit.
We grow all our garden stuff in troughs and rings since growing in the soil requires too much water due to the oven effect in the summer where the near surface rock heats up and radiates all night drying the soil making it necessary to water daily. I'm on a private water well and not terribly enthusiastic about watering anything every day since it seems like a waste to plant things that won't grow without a lot of babysitting.
I also collect rainwater from my greenhouse roof and use a solar/battery setup to drive a water pump inside one of the tanks which is just a standard plastic rotomolded tank. The other tank I have is a stainless steel tank that I got for a song since it leaked like a sieve due to design issues. I can testify that flex-seal tape doesn't work. I sealed all the joints since all were leaking and every one of them developed leaks past the tape. The only notable difference that the flex-seal tape made was in slowing the leak enough that fine particulates began to accumulate in the leaky spots and that has allowed some of the largest leaks to become trickles so that the tank will now hold water. I believe that it will eventually seal itself as all the crud tries to escape the tank and ends up forming a nice organic seal. Big win for me. I just need to put a pump on it now and extend the line to my orchard at my hugelkulture berm.
You have a bit of cedar there. We use cedar mulch to control weed growth. It is an effective weed inhibitor where we have laid it down. I have tested cypress, cedar, and hardwood mixes and cedar definitely controls everything better. We have our annual weeding process set so that we take a few hours in the fall and spring to pull about 95% of things we don't want and then over the growing season we just spend a little time yanking new growth if it happens.
You can and also should incorporate composted grass clippings (weed-free or cut from an area with native grasses and flowers). This will help build rich soil too. Avoid anything from a place that has an invasive plant problem. I am eradicating several non-natives from my place as I slowly drag it back to a native plant property. I have an area of the garden that is set aside as a pollinator attractor and it is full of natives that keep it alive with bees and insects from spring until the first good freeze. It's really rewarding to step out and hear the activity as you stand under the blackberry arches that are loaded with berries and blossoms waiting for the bugs.
I'm gonna check out some of your work, especially the Arduino controlled pump setup inside your greenhouse, since I would love to monitor my own usage from the tank.