This preseason will be the biggest yet and completely meta shifting in every way.
Pretty sure between the changes to mordekaiser, and items like rite of ruin on black market brawlers, riot is preparing to completely shift marksmen away from being in a static role, I would bet on it.
And as for the armor nerfs, I don't think they will be that significant. Randuins now gives 10% crit damage reduction, and we know for a fact that riot is going to rework all the ADC items as well soon enough, so I would not jump the gun on that.
I still agree that riot is doing a lot of crazy and possibly stupid shit, but I think come preseason, a lot of it is going to make sense.
Maybe I'm being a bit of a riot apologist, but I'm just saying, I'm pretty sure preseason is going to be insane.