Hi this sounds like a good project
Great sized tank but that is still too many cichlids, I can see what you are trying to achieve though.
The top three rows are probably good to go, the Chocolate, Blue Acara, Red Heads. But I think the numbers of the Keyholes and Festivums will cause issues. Neither are particularly gregarious, the keyholes are peaceful enough to exist together but not naturally social like Geophagus species. Festivums have a reputation of being good in a group but I've never met anyone who has kept them that agrees, myself included. The Chocolate will likely spend most of their time in the upper levels of the tank through the day, mine used to stay in the top third through the day then retreat to a cave on a night, quite funny to watch as he did it every night.
For me I'd leave the Keyholes out, they are the smallest fish and being so timid I think the bigger fish would scare them. You could look at 1-2 Festivums but I think 9 good sized cichlids with the Choc, Acara and Red Heads would be a great combination.
You also need to think about the community you build around them, having dither fish will help break up aggression and give the fish confidence to be out in the open more. I like to keep things a bit biotopesc if possible so I'd be looking at things like medium sized Characins like big disk tetras like Bleeding Heart Tetras or Columbian Tetras. Other good characins are things like Hemiodus, the Red Tailed ones are great! Headstanders are an other good shout with marbled and Ternetzi being the best IMO. Catfish wise have a look at Brochis, Flagtails and Hoplos for a good group, Pictus could be an option but might be too zippy for some of the cichlids. Any of the L number plecos would be nice, a big fancy one like an L25 or an L95, or something a bit cheaper like an L14 or L190 would be nice too. Whiptail Catfish are a favourite of mine Sturisoma are always a classic but Lamonicthys and Planiloricaria are incredible fish!
Wills