Not a huge fan of inserts and I end up tossing them more often than not but the basic Res Aracana insert is one that I find exemplary. It doesn’t make the box larger than it needs to be, it has room for both expansions and most importantly it serves as an ergonomic storage tray during the game.

I’ve seen third party inserts that looked tempting but they were too expensive and organized things differently from the way I liked. In particular I like to bag together everything that a given player color needs for their setup, that way I can just hand everybody their own bag for their personal setup.

My favorite accessories are a couple of very cheap sectioned trays that I use as component trays for almost every game and some simple card holders for games that need it.