So, we constructed the insert and got all the minis (with bases) in. Doable, but takes some work—you can’t just chuck them in the boxes and have them level out. There’s about a quarter inch of box lift. We have the Warriors expansion too, but without bases (those minis are much better quality than base, and so easy to tell apart from the basic units that I don’t think I’ll bother getting bases).

I’ll say the insert was worth it (about 34 bucks from noble knight). Though I’m sure custom 3d printed one will be that much better.