A decent idea. But mad speed probably isn't the way to go. With 0 Speed EVs and a neutral nature, Scolipede hits 240 speed before a boost, and 360 after. I believe the magic number to outrun all base 130's (the fastest pokemon you're likely to see in OU), is 264, or 96 EVs. Basically, if you want to hit this benchmark, you can go 160 HP/252 Atk/96 Spe, which has the added benefit of hitting 301 HP, which is a good number for switching into Stealth Rock, playing against Night Shade/Seismic Toss and Life Orb.
Well, technically, its a "buff". Breloom is going to be significantly less common this meta with talonflame, fairies, grass types being immune to spore, etc. I'm not sure about switching to Rock Tomb as a Low Sweep replacement. Force Palm is available as a less reliable, but more permanent alternative, particaularly since most stuff switching into Breloom fears paralysis almost as much as sleep. Superpower will be available post poke-bank and part of what made Low Sweep great was that it lets Breloom hit the switch in twice while sporting repectable power (my emphasis). Breloom also doesn't have to run technician, Poision heal is still a pretty great ability, and Breloom does have access to Stone Edge.
Bottom line, Scolipede has bigger fish to worry about than Breloom. Its main issues are going to be moveslot syndrome and switching into anything that isn't a resisted or weakn neutral physyical hit. That being said, with Blaziken gone, it being undoubtedly better both offensive and in utility than Ninjask, I believe it will see considerable play as OU's speed passer.