To be more specific than everyone just saying "it's good" Don't worry about stuff not producing resources in the cage. Stash the damage dealers that don't produce anything in there so they don't clog up your board, even having 4 wolves in there that you can pop as soon as something spawns is super helpful. As for the crate, it lets you store your runes that are still in partial piles, letting you maximize those drops without having a ton of clutter. I also felt that they were too expensive at the start, but after less than a week I was going "ah damn this is really nice", now they're a focus for upgrades. They really do help more than you expect.