Planetary Coronagraph maybe?

riklaunim

Solar telescopes may use Coronagraph to cover the Sun, but a planetary Coronagraph could be used to cover the planet to catch Mars, Jupiter, Uranus, Neptune... faint mini moons, or Uranus and maybe other rings... Concave semicircle could be used to block Venus day side to catch Venus night side easier and with better detail.

Some already played with that idea: http://beloptik.de/de/left/planetary-coronagraph-planetary-moon-viewer/

However it's rather way more complicated than ADC ;)

Sam@ZWO

but seems too few amateurs may have interesting of this ;)

riklaunim

Maybe a ADC-demand effect will kick in? :) Who knows. Estimated price can answer a lot of questions and estimate how many people would be interested.

Northern hemisphere in the upcoming years will be almost planet-less, aside of Neptune and Uranus, so doing funky things with those two will be some sort of an alternative.