I would recommend something like this:
It will let the expanding air out, without letting in new, it will remove the need for you to always have to open it and let it burp once each day or so. Very handy. Also I’ve seen some places also sell two stone/clay halfcircle weights that you can slide down through the opening and that weighs down the kraut below the brine so it doesn’t mold. Other than that it might be good to have 2 jar sets so you can rotate and always make new, and you might need more, depending on how much/fast you plan to eat it once you get accustomed to it. Otherwise I suppose you can get bigger jars as long as that lid fits, and the weights if you decide to get those.