What if you could buy 2 shoes?

and it only took up one item slot.

What I mean by this is something similar to how Viktor's hex core works where you buy extra levels to get extra effects.

EDIT: This would be limited to 2 in total even for champs with 4, 6 or 8 legs unless Riot wqanted to balance Hec and Elise around this. Also it can not be 2 of the same tyle to prevent excesive attack speed or magic pen. thanks to JavelinJoe for makign sure to bring up the issue of this having no limits.

So if you want to buy boots of Swinftness and Ninja Tabi you can and you get the stats and effects of both

I know movement speed on boots would likely need to be nerfed a little for each on on it's own but sat boots of speed gave 20 instead of the current 25 and the boots that have + 45 increase movement speed by 15 each. (merf treads, ninja tabi, ionian boots, beserker, sorcerer) buyign 2 of these would result in 50 movement speed 20 from the base shoe and 15 from the 2 other shoes.

boots of Mobility would provide 90 movement speed out of combat and Swiftness would give +25 passively with the slow resistance.

All of the boots keep their current unique passives and stats be it +35% attack speed or 30 armor.

This is similar to how the removed boot enhancements like alacrity or Captains were bought but instead of being some add on it is basically buying another shoe for the other foot.