Do I need upgraded power cables?

Yes, people often don’t hear a difference when they "know" before that there cannot be any difference...Pass Labs includes very good quality cords, many companies do not...a nice bonus too is that used power cords are avilable at good prices and hold value a long time...I ended up with after market cords after extensive A-B testing with a friend (all cords were loaners, with free, simple return)...neither of us knew anything about power cords at that time...

@bzawa - cabling- you’re on the right track, it’s usually best to upgrade from stock cabling but don’t go crazy.  Many believe that the power cable is the most important cable.

Agree you should also consider a better conditioner for further sonic benefits

I had tried upgraded $100-300 power cables in various components, but didn’t hear any difference, so I did not think power cables really made a difference.

Check WTPC v2 (sale for $250 in Agon). I can hear clear sound difference in comparison video. Alex/Wavetouch

3 PC comparison - JPS, Zentara, WT (click time stamps)

There are times though (especially in dense musical passages) that the sound is stage is a blur - as if of all the instruments are coming from the same place.

Coming into this a bit late, and forgive me if I missed any comments to this effect, but I can’t get past this comment by the OP. Yes, it could be a lot of things, the recording included, but I doubt that a power cord is going to resolve this issue. Not sure if you favor vinyl or digital, but experimenting with cartridges and phono amps, or putting a good DAC between your CD player and amp might make all the difference in the world.

As for power, lots of good recommendations, I have had good luck with The PS Audio regenerators. It was not jaw dropping, but I achieved my goal of having “late night” sound any time of the day. This after using Furman and Puritan products. Amp still goes straight to the wall, it sounds better.

The recommendation for a direct line is a big one as well, if at all possible run a couple lines for your system. And take @soix’s advice, get a set of AZ Satori’s. I took his recommendation a few years ago, it changed everything for the better.

Cronus Magnum lll Integrated Tube Amp / Focal Aria 948 DW Speakers 
1. Rogue amps come standard with JJ tubes. These tubes are very durable snd quiet. However they are terrible as far as sonics are concerned. 
2. Focal Aria speakers are really nice. They’re actually warm sounding. 
3. Kimber cables are a decent match with this gear and I wouldn’t touch them

Replace the JJ tubes. Start with 12AU7. I really like Brimar Cv4003 from upscale audio. These tubes should transform the amp. Then tackle the 12AX7 and try Gold Lion. You can also experiment with power tubes. But I would do the signal tubes first. 
Plug the amp to wall skip the power conditioner  

Address the cables later.