This is my take on a full insert for the Minecraft Builders & Biomes board game. The goals with this was to enhance setup and play and provide solid storage option (with no bags). If looking for just a board to hold the main tiles during play, obviously can just print that if you like my design. The largest component requires ~200x200mm build surface. No supports needed. Magnets: My design utilizes 6x3mm circular magnets (6mm being the diameter).

These GBYMIUY Round Refrigerator Magnets have worked good for me.

The spots for magnets are designed to be tight fit, for me a little force was needed to get magnets seated, even with the tight fit, the Magnets should be secured using super/gorilla glue.

Components

Main Board Section(x4): 198x198mm - Designed to hold the 16 stacks of tiles during play. And tiles can be stored in these as well if desired to create fast setup next play session. Utilizes magnets to "snap" together the 4 sections to create the 4x4 tiles board during play. These produce very distinct "player spaces" during play, which was a goal, also all four sides of the tiles are exposed, so can flip them from any angle easily. Two sides of each board section has 3 places for magnets, but I suggest forgoing putting magnet in middle section as just using two magnets per side worked good for me. Magnet orientation: Important care should be taking that magnets are positioned with proper polarity so the proper sides attract to each other. The trick with getting magnets right is to stack all 4 sections so they are oriented the same way. Then one side of that stack should all have same polarity, then the other side all the opposite of the first side polarity. One way to consider this is the same side of a given section will never "butt up/need to attract" to that same side on another section. Getting the magnet's polarity correct can be a little brainteaser. Player Item Holder(x4): ~33x~44mm - This is a component designed to hold one set of Player token, score marker, and five starting weapon tiles. Idea is these can be handed out to the players easily before play. Block Holder Base and Sides (2x each): 160x98mm - Designed to store the blocks 4x4x2(high), but the base and the sides are separate components, utilizing magnets to attach and un-attach allowing the 2 side components to stack, creating a "form" for building the 4x4x4 stack of blocks for play that is then lifted from base, and then the stacked sides can be attached to the second base to form a discard holder for the blocks during play. The base, top, and bottom each can take 4 magnets, but for me, two was enough in each, I placed two magnets diagonally each on base, top and bottom of sides, making sure they aligned. Magnet Orientation: Here we want both bases and the top of both sides to have same polarity, and the bottom of the sides to have opposite of base and top. This will allow the sides to "snap" to both the base and the top of the other sides piece. I printed these with a higher infill (I think I chose 30%). Player Item and Weapon Holder/Player Aid-Score Holder/Board Tile Holder (1x each): 170x88mm(largest) These three components hook together and form an insert that goes and "stays" in the box. Giving place for the Player Item Holders, Weapon Tiles, Player Aid Tiles, and optional place for main board tiles if not wanting to store them in the main board sections. These also fill space so things don't move around during storage and provide support for storing the Main board sections. I printed these 3 with 8% infill.

"Player token set" results