Recommendations for a good power conditioner? Do I even need one?

I'd upgrade the power cords and outlets first.
Next would be an inexpensive but you will hear the difference with the Furman PST-8. Shop around for your best price including looking at Amazon. Well under $800 but produces better results than many power conditioners costing $2000. The AQ Niagara's are also very good but cost significantly more.

I went with the simpler is better concept and parted with an old PS Audio P300, and replaced it with an almost equally old BPT power conditioner. My choice in effect stayed the same, i.e. I value the betterment that balanced power has to offer. The PS Audio regenerator was good in service, but is quite complex internally, and the BPT did much of the same thing as far as balanced power goes, and only uses a very beefy transformer plus other appropriate parts. 
 Richard Grey products do have their place in my system, yet probably in the source end of the system.

tried lots of stuff, settled on Furutech passive power strip and Cerious power cords and cables...

I like what the High Fidelity MC-0.5 passive conditioners do for me. Right now they're 35% off, which is the price I paid for three of them.

All the best,
Nonoise

So I bought a Furman PST-8. My existing power cords are an Acoustic Zen Tsunami on my Pathos integrated and a Transparent Audio Reference on my phono stage.

The Furman reduced the noise floor a bit but what was odd was how it brought instruments forward in the soundstage. I confirmed this with some blind tests with my wife. Instruments on good acoustic and jazz (and even a few rock and RB) recordings were closer.

Anyhow, I'm happy with it. For less than $100 it was a a worthwhile tweak.