Sounds like its going to be quite a journey.
24 pots as well,,,
With all the pots, leds, switches, LCD display and of course the rotary encoder, is to think how all this will interact with the Axo. I expect with a lot of extra IC's etc, it could all be connected to the Axo directly, but this could take up precious resources from the Axo. So then the next thing to consider is maybe using other micro controllers to assist, Arduino, teensy etc.. This way you will have access to more GPIO's to connect all your Pots, Switches, Led's etc to. Then how will this all communicate with the Axo, for example you may want to use midi, even if it is all built internally, you can still connect them together using midi.
Just some things to think about..