Luckily, fixing that problem was easy, only using material and tools I already have. I used a scrap piece of quarter-inch ply, and cut down an old bowed 1 by 12 to make the inset frame, the result is pretty nice, if I do say so myself:
One side has small indentations to clip the boxes from my Stanley storage that hold the focus, evade, and stress tokens. I will be printing the appropriate logos on the boxes, just to make it easier to pick from the right one.
The other side has an indentation to hold the dice, though I'm pondering whether to make it deeper, to make sure they don't wander:
Facing both players are stamps representing the three factions. Scum came out less than perfect because the logo doesn't scale that well to 4 cm for sponging with all the intricate details. I should have made the imperial logo grey too, just so it doesn't stand out as much. At this point, I'll live with it, it's meant to be a play surface, not a work of art!
And a closeup of the texture I painted. I wanted something cosmic, but not as distracting tothe actual minis as many I've seen on YouTube:
It is super-glossy by design, I wanted the black to pop. Sliding minis is the last of my concerns, my main opponents are 4 and 6 years old 
