Stealth Rock is kinda overpowered.
Spikes is fine, they're not so bad. If you could afford to spend 3 turns setting them up your opponent kind of deserves to lose anyway (just like if he gave you 3 turns to set up Quiver Dances or Bulk Up or Nasty plot or whatever). Spikes are a little easier to get up than those because you can switch out and set them up as your opponent sends in something to check your Spike setter, but they aren't a immediate a threat as, say, a Volcarona after 3 Quiver Dances, or a Mew after 3 Nasty Plots.
Toxic Spikes are okay but they're a shitload easier to deal with since Poison types (typically another toxic Spike setter) can absorb them. If everyone ran, say, Tentacruel to set Toxic Spikes and to absorb Toxic Spikes with the same pokemon, it could get a little bit centralizing. All it really needs is a retardedly good Toxic Spike setter and Toxic Spikes become their own weird little economy of uselessness that also destroys anyone not buying into this uselessness economy. I could see it warping formats under the right conditions.
Sticky Web is stupidly good against the right stuff, but its failure to stop flying types and levitate users (often some of the best fast threats in the format, the kind of stuff you'd want it to stop the most, like Landorus, Lati@s, Azelf, Charizard, etc.) makes it really inconsistent. Sticky Web can be defeated by preparing for it even a little, and you can often have something that fucks up a Sticky Web team on accident, so it really isn't that overpowering. It's in the same league as Trick Room, massively hoses HO but not that great against everything else.
>>33973121I seen Toxic Spikes do all right in VGC before, it goes well with Protect spam and Fake Out shenanigans.