I've quit taking your traditional PWO and just take 200mg caffeine with some beta-alanine on it's own. Much cheaper and I don't feel a difference.
Other than that, creatine is THE staple. And some protein if you need to supplement to hit your macro goals.
I also take some BCAAs a few times a week. I honestly have no idea if it's effective or not, any studies I've read are inconclusive on its effectiveness. But I like the flavor and it's not expensive.
Other than that....