Blue cats do fine in ponds, they just don't reproduce well in them. For trophy cats, you don't want reproduction. If your sole goal is trophy cats, I'd still go with the blues. Hybrid catfish don't have any higher tolerance to low DO than do CC and blues that I know of.

I am still a huge fan of pellets and golden shiners for the first 3-4 years, then at year 4-5 stocking gizzard shad. Some RES may be a good addition to help keep parasites down and an additional forage for the cats. If you decide to add some flatheads, the addition of BG may be good forage as well, but flatheads love to eat gshad as much as any spine rayed fish.