Do Boots of Swiftness need a buff/new effect?

The only champions I ever only see buying these is . Even when in theory Swifties should be a good/right choice, bully it out, or even .

I think they should raise the slow-res to 40% or 50% or give it an effect that lets you move faster either towards or away from champions. Maybe something similar to Spectral Waltz passive but for non-Marksmen?