Cassiopeia can't buy boots..

http://www.surrenderat20.net/2016/03/325-pbe-update.html

According to a leaked and I think live pbe update, cassiopeia's new passive is she gains movement speed per level but cannot buy boots.

I get the whole idea of her not having legs, but we have several champions in this game without known legs, or just float around and never stand on them. (Notably, nami, lissandra, malzahar, syndra, vel'koz, karthus, corki, kassadin, etc)

Moving on from a logical stance..

Im worried about one thing particularly, and that's denying cassiopeia of any bonus effects the boots provide. Is her base movement speed from passive enough to make up for her lack of boots+alacrity enchantment? If she wants to go boots of mobility or swiftness, would the passive make up for the bonus speed? Would she be able to build magic pen easier with lack of sorcery shoes? Is zhonya's her only hope against AD assassins rather than ninja tabis?

I'm just curious as to how major the passive bonus is exactly, as it seems kinda good in theory but in put in gameplay a bad idea. I get it's wip but if this is what the plan is riot may need to rethink this while it's wip.