I like that cadweld splice, I just used a grounding clamp.
How did you sink the ground rod? I used a 2 lb hammer for a good workout to drive my 8' rod into the ground.
I've read up a lot on grounding principles and know that having more than 1 rod can be problematic. I didn't want to risk bringing lightning into the house so most of the system is on the house's old ground but I isolated the combiner box from the panel rack and grounded the panel rack and panel frames to a separate rod.
I also moved the electric fence to a separate solar powered charger so the fence couldn't act as a lightening rod.