Ever since I started using shulker boxes, I've had to empty my shulker boxes and repack them when moving them to other smp's. Not sure if this bugs anyone else, but I find it a little irritating, and w as wondering if we could somehow get shulker slots. Like instead of a vault page, you can just store a shulker there instead.
Nah, it shouldn't be impossible. Maybe on the Empire, but if you take into consideration that you can fill up your entire enderchest with shulker boxes, and that this "enderchest data" is stored in your own personal 'profile'... trust me: that can easily turn into a huge pile of data to process (fun thing is to check this on 1.13.1: /data get entity @p EnderItems, you'll see what I mean). Still, it wouldn't have to contain the actual shulker box itself. I could imagine having a separate vault page which is the size of a SC + one slot for the shulker box. You give a command (or alt-user the shulker box (?)) and then the contents of the box would be examined, moved into the vault page individually together with the (now) empty shulker box. It would definitely make things a bit more accessible because if you pick up a full shulkerbox on a server which isn't your home server then you have no other option but to head out into the waste to empty it and move the items into your vault. I know from personal experience that this can be quite a hassle. +1 from me.
Yes. Shulker boxes in vaults is possible. There is a change I need to implement before we can consider it though - as there are some technical limitations with how things are currently. With my anticipated change (in the future) - I think we will be able to allow shulker boxes into vaults. No separate slots necessary. There are actually 2 things I need to implement - one of which is for our plugin to be able to look into the shulker box while it is still in item form.