Questions from a Tube Preamp newbie

@lous One current tube brand you may want to consider are Genalex Gold Lions sourced from Cryoset. I have yet to find any 12AU7s that work as well in my line stage as the GL’s. besides the fact that they have a neutral, dynamic, open sound, they last a l o n g time!

I've heard good things about the gold lions

Unless someone owns the same preamp, recommendations may help, but a different circuit will result in different sound.
I had a preamp that used 12au7 that was meant to stay on 24/7, it has been so long, I can't remember what I was running. But those tubes, in that circuit lasted for years.
I mostly wanted to comment on CJ, the preamps that run 6H30s, I have one a CT5, are easy on these tubes, I just replaced the tubes for the second time, after +7000 hours, and if they had deteriorated, it was so slight as I could not swear to it. The 6H30 is one of those tubes that there are only 3 options. NOS, hard to find, and if you do, a minimum of $250 for a pair, if lucky. The EH gold pins from Cyroset run me about $90, shipping included. I found about 75 hours to settle in. They get a little bright around 50hrs, then by about 75 hrs, they are done.
I used to have a preamp, that used 6CG7/6FQ7, that I rolled at least 10 different tubes through. At that time, almost everyone recommended RCA Cleartops, I found the RCA Blackplates, Toshibas, and the winner to be Mazda. If you can find someone with the same preamp, their advice will be most helpful.
Maybe I am a minority, but after a lot of rolling in two different preamps, I got tired of it. I prefer to listen to music, not tubes. My CT5 makes that easy. No fretting over is there a better choice.

I have NOS Mullards ECC 82’s , sounds like somebody threw a blanket over my system . Kinda like pushing the Dolby button on a cassette player .

As always, YMMV.
Regarding Mullard and other NOS brands, if they are noise-tested they should sound good for many hours. There are several types of Mullards; longplates, shortplates, ladder plates, with square getter or with halo getter. ECC82 labelled "Made in Great Britain" are of the highest build-quality.

There is a "house sound" to these tubes, warmth with a relaxed top-end (since they are British they should be called valves).
1950’s ECC82 longplate square getters present open and warm sonics with rich textures; I own several pairs. The CV4003 is a military-spec boxplate with a wide soundstage, and to my ears, sound more "lively," whereas the short plate sounds more "closed-in."

Philips tubes made in the UK factory will have the same sonic signature as Mullard. Phillips Holland was the parent company of Mullard and Amperex.

Regarding #4, JJ tubes do not have a good reputation among audio tube people.  However, Rogue may have built their preamp to sound good with them and if it is hard on tubes, JJs may be stout enough to handle the punishment, while other tubes may not.  Best bet is to talk to Rogue about it.   See if they recommend any other tubes.