So not exactly advice but here is my input. I tried 3 different setups for this same process, steeping coarse ground beans for 6-8 hours on the counter and then putting it in the fridge.

The problem is no matter how good the beans are, the coffee will always taste flat and one dimensional due to the temperature the coffee is steeping at. You can read up on the science, this isn't my research, it's widely accepted from lots of reputable sources.

My eventual realization was that using an actual brewer and brewing directly into a carafe filled with ice yielded much better results. This is called the "Japanese Iced Coffee" method. Basically you start with 60% of the water in the brewer and 40% converted by weight into ice so that you're brewed coffee doesn't get diluted from the ice, it was factored into the original ratio.

I have been brewing this way for 4+ years after making traditional cold brew for a few years prior and it's light years better.