Hi there,
I totally agree with this suggestion, because at the moment when you change Chest Items to (for example) Basic chest items, and you select the Tank or Healer kit, you get an advantage, because those items are not even in the basic chests. I currently only see a purpose for having a Kit Selection if you are using the Normal Chest Items or the Basic Chest items right now. When you are in the Basic Chest Items you don't really have a choice to pick a kit or not, because most other players would have picked either the Tank or the Healer kit, so without selecting either one of them, it isn't exactly fair for yourself.
The way it could work, is in the Kit Selection, instead of having the descriptions say (for example), "20 bricks, Chain chestplate," it would just say what category it is, for example "20 building blocks, Chestplate". But the image on the right-hand side of it would be an image of what those blocks would be, which would be a picture of both a wood, brick, and endstone block (the three variations of a "building block"), and possibly the variations of the chestplate (Lether, Chain, Iron). That way, people can still vote for Chest Items without having the kits change around afterwards.
Great suggestion, really hope this gets implemented, on EggWars too :).
Just to mention, a thread containing the same idea was posted recently. I've just reposted what I said in the thread, but in the future make sure the suggestion hasn't already been posted. :)