Texas is a big state. I am in central texas. There have been 2 years where we got 12" of rain in a weekend. Those 2 years
led me to raised beds cause my potatos rotted in the ground. After i went to raised beds we haven't got that amount. Lol.
On the gravel, its hard to explain. As the water level drops, the voids are filled with air. As water is added, that air is forced up through the soil. Without those voids its like a soggy swamp. Aerobic vs anaerobic. There's a YouTube channel. I think its called "gardening with leon". He strsses that the water level
should be 1" below the top level of the gravel (or corrugated perforated pipe, which he uses). This leaves an air layer that breathes up and down. You might watch it, see if it makes sense to you.
If this is working for you, go for it. Just bringing this up for consideration.