I've tried a few different options on the AP16. The Huggett Atom is okay, but not quiet. The Huggett Astille is the most quiet I've used with the AP16.
Luckily I had bought my AP16 from Krale and it came with the Ataman moderator. With some selective re-arranging of the baffles and added some wire and fabric I've made it quite effective for it's size.
I haven't tried a Huma Mod30, but I imagine a 2/0 or 3/0 would do well.
I don't think getting a DFL Sumo is the right way to go. A Koi would be beyond sufficient for the power output.