Merge Solo/duo and flex rank
I think it would be cool if the ranking you have in solo/duo, was the same as the one you have in the flex ladder. The queue should still be different from each other though, so that when you queue up for solo/duo you would still only face players also queuing for solo/duo, but you would have the same ranking as the flex queue and vice versa. The reason I suggest this, is because for me it is quite annoying that when I play flex with some of my friends(we are all bronze...lol), we often face players who are plat in solo/duo. To me this makes no sense, because it is still the same game mode overall.
another solution could be, to let the solo/duo ranking affect your ranking placement in flex and vice versa(no idea how this should work though).
So what are you thoughts?