What's A Good Upgrade From A Manley Steelhead?

I have Chinook SE, not a Steelhead, with a Bob's Devices Sky 20 SUT and a Hana Umami Red cartridge. Adding the SUT was an improvement.  I'm very happy with the results.

I am not one for cliche's but you would have to wrest the Steelhead out of my cold dead hands for me to give it up. It is seductive and rapturous when given a decent set of grooves. As I type this I am listening to the remastered version of Kate Bush's "Hounds of Love" with a Reed 3P arm and Lyra Etna Lamda. Drive is a highly modded Garrard 301. I don't for a minute disbelieve that the CH Precision, various Allnic units and more deliver something that can be called "better". But if your Steelhead is holding you back than you have Fifth World problems-assuming your TT is set up optimally and assuming you have heard it with good pressings. My Steelhead is dead quiet, dead reliable, and so satisfying (to me) from every perspective. After 2000 hours I did re-tube it with tubes supplied by Manley Labs which were very reasonably priced. 

@rooze I am responding because I have the same Audio Tekne MC-6310. It was sent to Imai-san in 2021 for cantilever repair and returned much improved. It is paired with the Audio Tekne MCT-4818 SUT going to a Sun Valley tube  phono. My phono is not of Steelhead caliber admittedly and your OP is about phono preamp. But I have two other cartridges, a ZYX Ultimate Omega and recently acquired Transfiguration Proteus. Both cartridges go through the AT SUT into a lower level phono stage than yours. And with the Proteus, I feel that the vinyl front end will stay put for a while. 

Perhaps adding a higher caliber cartridge might be a the other way to go? My apologies for veering off topic.

@fsonicsmith1 I agree it’s an excellent phonostage and I’m sure it isn’t the constraining factor in my analog setup… just interested in trying something different. 
@ledoux1238 yes, a different cartridge is on the list. I wanted to upgrade the arm first, which I did last week, then find a good cartridge that works well with the new arm (Graham Phantom). I regret selling the Audio Tekne. I also sent mine back to the factory for a rebuild and it sounded great.

@rooze There have been times when I thought the Steelhead might be holding me back from pure listening bliss. The culprit proved to be one mediocre pressing after another. Perhaps a present-day state of the art phono stage would have made them sound more appealing. In fact, I don't doubt it.