My gaming group plays Eldritch Horror with the Mountains of Madness expansion quite a bit and I have devised a way to organize the plethora of parts in such a way as to streamline setup from a 45 minute endeavor to less than 5 minutes.
This project is based off of
bageezus's game insert https://www.thingiverse.com/thing:2779019
nogardtla's Eldritch Horror Medium Box https://www.thingiverse.com/thing:3009975
heavily modified to fit my particular setup. In addition to the 3d printed parts I also use
Box 1 from bottom to top:
2 stacks of 2 player trays each go along one side of the box
Next are the box trays. BoxTrayPlayerCards and BoxTrayGates go opposite the player trays. BoxTrayTokens goes on top of one set of player trays.
On top of the BoxTrayTokens are the three condition card trays
On top of the remaining set of player trays go the 2 large card holders
The remainder of that box is filled with gate holders and a small dice bag that I use to hold clues
both game boards, rules, and a crown royal bag full of the regular monsters
0.2 mm for everything but the gate holders, .15 for the gate holders
I used a single layer of brim set to 5mm for each of the prints to help cut back on corner warping.
4 player trays (or more if you need them, any more than 4 will need to go into box 2)
2 Eldritch_Horror_Conditions_Rack_x11 Print 2
and 1 of everything else
Also shown are the gate tokens from https://www.thingiverse.com/thing:2102228