I loved the design of this Marvel United Base Insert (https://www.thingiverse.com/thing:4758676) by MikeMennillo (https://www.thingiverse.com/mikemennillo/) because it can hold sleeved cards, all of the included tokens, and preserves the original display for the miniatures. I made the following tweaks to that design:

• Added a bottom to the fancy card tray
• Split the two four-slotted token trays into individual token trays (and one small tray divided into two slots)
• Added spacers under the miniature display to prevent the trays from sliding into the display. This allows the display to remain in its original position instead of needing to be turned around.

Notes:

• IMPORTANT: This insert requires cutting the original insert. I used a combination of scissors and a hobby knife to cut the original insert and cover.
• I used Gamegenic Standard Card Game Prime Matte - Gray sleeves (66 x 91mm). MikeMennillo mentions using Paladin Percival Sleeves.

Printing instructions:

• Print card holder: I used MikeMennillo's 'Fancy' card holder design. That page has a 'Simple' card holder design if you prefer to have your cards stacked in two rows.
• Print token trays: There are several configuration options. I use 7 single slot token trays and 1 tray split into two slots for the smaller quantity tokens. 8 single slot tokens trays will work fine as well. MikeMennillo has the 2 bigger four slot trays if you prefer that configuration. My trays will stack well with each other and MikeMennillo's stack well with each other but I doubt mixing the two designs will work.
• Print the spacers: 1 left spacer and 1 right spacer. The right spacer is design to hold the token trays and locations in place.