Recast spells is my personal favourite topic in this matter. Instead of giving us new icon that will be placed on first aviable position (and yes, im aware that if you know this, you can adjust your actionbar so you know where it will appear ... that is what i do btw) it would be MUCH, MUCH and once more MUCH better, if this new "recast" spell would simply replace the spell icon, or join its upcast in popup window)
Yes! Absolutely! Playing icon hide and seek is a pain, as is recasting a spell with the wrong button. I'm aware of the empty slot trick, but the slot gets used up if you add anything to the hotbar, such as a newly prepared spell, the ability from a new item, etc...
Or, you know what would be even easier? If we had a single spell button that pulled up a pre-organized window of prepared spells listing them in order based on spell level and alphabetical, and yeah, if you need to recast, it replaced cast. Instead of tossing everything on a hotbar in random order... Ah... order!
But this is distracting from the original post. The only reason I mentioned it was because once we get higher levels, this game is gonna be a mess of issues if they don't implement more 5e. Scrolls will become even more confusing as to which scroll should be available for which class.
Limitations bring balance and order. Homebrew brings more chaos and imbalance. In a game like D&D, the more homebrew, as you get to higher levels especially, the greater the mess.