While this may seem like a controversial suggestion to some people, I think it would add a combat dimension if it was possible to interrupt weapon swaps. Let’s say the swap has a one or half second cast time, playing the animation to stow the weapon, then switching weapons and playing the animation to draw the alternate selection. If interrupted during the stow, the swap would not occur and you’d have a cooldown of some well determined length before you could use the ability again.
There could be traits or buffs that reduce this cooldown, but overall I think it would add some value to the ability, and it would add some means of breaking combinations that involve a swap. Well timed interrupts could give you an edge and provide some more dynamic decisions to be made during combat. I think it would also open up the door to making weapon swap sigils a bit more interesting and powerful.
Naturally, the elementalist attunement would work similarly. There are also options to give some traits immunity to this. For example, maybe there’s a trait that doesn’t allow you to be interrupted when switching to water. Or from a particular attunement. Having to make this a decision could add some flavor.
This is just the basic thought, but having pondered about this for a bit, I think one could add a fair deal of depth to this. It would have to be metered properly, but all in all I think it’s possible and at least to me it’d make things more fun.
Think of the possibilities.