Quick Switching In Practice Tool

I thought of an idea where instead of having to switch champs/runes/masteries/summs by exiting practice tool, they could be in the practice tool toolbar on the left, one block for each different category. When a certain block is clicked, one gives you a list of your available champs, another one will open your masteries, another with your runes, one with all your available summs. When selecting a new champion, your items/level/bounty count will stay, but the health and mana/energy/etc bar will reset. I also think levelling down should be a thing, to see how powerful your build is at your level. I think this would be more convenient since the loading screen takes quite a bit of time for some people, plus, it's effective if you want to try a bunch of different things at once.