There isn't only one way to run things, sumwun. Gyro Ball has a very limited amount of PP is my main concern. It crossed my mind, but I'm not comfortable with that.
Spikes is a good option, but there isn't a clear cut better or worse option here. That would depend on what your team looks like, which is what I didn't cover here because the information for such a request was not provided. Thus I prefer the more annoying and potentially permanent condition of Thunder Wave. Besides, if you wanted entry hazards, wouldn't you use Stealth Rock?