Ah, though to answer your question, yes. I have had a couple 6 healer and tank comps.
Either way, I think if Quickplay and a Quickplay Classic were shown side by side, it would help make QPC more populated and fun, while also reducing QP222 queue times 
That is entirely possible
Why would any solo Q tank and to some extent support ever want to play QP classic. Maybe if you could sell tank runs like in WoW but otherwise no way.
Made a new GIF
its what mega desires!
Sadly this won’t matter if/when they rebalance the game around 2/2/2.
qp classic is exactly the same way it was before, people don’t care for any kind of structure and so you have to forcefully adapt to whatever 5 dps players want you to do
I am a flex player dude, one that does that swaps that tend to win matches like 90% of the time but it is what it is.
Its not about giving the choice, its about dividing people in queues. If your goal is to shorten queues, then everyone has to go through the same queue. Period.
If you add another one, everything will be worse. LFG was added and look how it went. When people are given the choice to work for it and make the game cater they needs, they are lazy and choose not to.