A tough problem I've came across, as a knight who has almost 3,000 hours sunk into Spiral Knights, and something I can't overcome mentally is that. . .
While having extra Weapon Slots activated (which I always "have" to have a 3rd so I buy one every month as long as I'm active, along with two trinket slots) I run into the problem of not being able to figure out which weapon is where in my equipped slots, and consistently throughout the years have to scramble through my scroll wheel selection and pick out what weapon I'm trying to look for.
Even though it is only 3 or 4 weapons, trying to quickly swap when a knight needs to in a game like Spiral Knights, that short few seconds (or longer if we end up damaging ourselves in the process, or dying) can do a lot to/for a knight.
There's no permanent view of what weapons Knights have equipped in our client, and the only use of the Weapon Selection Wheel is for players who don't want/can't look easily, at their knight themselves to see which weapon they have equipped, but this does not help differentiating which weapon is which in our scroll wheel/bound weapon buttons.
We have to swap weapons to be able to view what slots hold each weapon. This adds to the time we take to swap to the weapon we desire.
There's also a delay with using next/previous weapon that makes it harder to fiddle through our equipped weapons, while we are able to bind specific slots to specific keys, this would jumble and fill up our keyboard very quickly whether we're using mouse movement or WASD controls, while we only have five or less stubby little fingers pressing buttons on our keyboard. With binding slots to keys, we would still need to go through the process of fiddling through to recall which slot has which weapon.
I don't really know what could be done to assist in this type of problem though, having a permanent weapon selection wheel in the center of our screen would obscure our view, placing it on the same line as our augments and consumables may make it too long and look poorly, possibly cutting off the edge for smaller screens, or placing it on the sides of our screens may be tough to make it look decent throughout the UI. Our knight and sprite icons in the top left of our UI may be fiddle-able to manage something like this, but I'd imagine that'd take too much work to cement together and may not be worth the effort.
I'd much prefer to have the "current weapon" icon somewhere in our HUD that's always viewable as well. The weapon wheel distracts me all the time so I simply don't have it on since it draws my attention away from what I'm fighting. Because of this, if I get cursed, I am 100% blind to what items of mine are cursed. Having your "current" item viewable somewhere on the HUD at all times solves the problem of not knowing what weapon is cursed, and also lets you know what weapon you currently have active for this kind of scenario.