https://leagueoflegends.fandom.com/wiki/Gold_efficiencyMove quick not as cost effective as toxic shot
about 33%cost effective it says.
33.3AP to replace 1rank in toxic shot insta-on hit damage*21.75gold value = 724gold value of AP (350gold value if take AD to get 10on hit damage) add a little god value for the base-DoT-damage
what you see here, is that fast attack autoattack damage gained from AP is 50%as cost effective as building AD-teemo (Nashor not makes it better then AD)
+/-5%movement speed for 1rank of w*39.5gold value = 197.5gold value
Problem is,
you cant spent 3600gold into deathcap and get 168AP in it, or even more
3600/39.5gold value per 1%movespeed = 91%movement speed items not exist
you need 40%movespeed items, to justify not maxing w
you not gone stack 10%movespeed items, and replace OP passives like Liandry/Luden for AP