I think the best way to create innovation in proplay (but drafting will become extremly hard early on) is to remove champions in a BO that were picked before the 2nd ban phase. Obviously not after because it is where we will see specific champions most of the time because counter pick, not flexible or very specific team comp that is a result of the whole draft before.
Obivously it will not change soloQ or BO1 draft but the second case can be solve if you know what i mean
These kinds of changes are super exciting for me, could do all bans are permanent or whatever too.
Complexity of draft is very dangerous and something that we'd have to be very careful of. (If draft is super fiddly and complex the pro game gets really hard to understand for most ppl, etc)