I have a yes-no oracle that combines 2d20 and a challenge die. The 2d20s give you the yes no element and the challenge die gives the and…, but…, and complications.
In addition, I have been building a mix of d20 and d6 random generators.
The more I muck about with the game, more opportunities I see here for constructing tools.
I am pretty sure I can construct the GM screens for John Carter in the next few days.
2d20 System
I definitely think this needs to be a single book that expands upon the tables on the screens but also provides the solo roleplaying support. The way that Modiphius has tweaked the 2d20 system to each game/genre is quite interesting. I had never looked at them back to back before.