Phono preamp or SUT for low output moving coil

Since my Krell KRC preamplifier with MM/MC phono stage lost one channel

I’m using Aurorasound by Lundahl SUT . Quite good solution for my situation. 
while My PA Krell 300 is getting refurbished I’m playing records with Rotel RA-1570 which has just MM phono. The Koetsu black MC cartridge is sounding very nice. 
no idea when my Krell amplification will be back and usable, I’m looking around for new rather used amplifier and preamp. It’s a lot of these things out there I don’t really have ability to listen different pieces of equipment. More likely to depend on opinions, reviews. Just a little hint, Krell was for me a little to bright, to “aggressive”I would truly appreciate any advice. I had opportunity to listen Audio Research Amplification and it was quite great, can’t recall the models name.

being an old timer I have old timer equipment and through all these years I got pretty attached to it however, some of it started to give up so I’m looking to either repair it or replace it but to your opinion, I agree that maybe it’s time to go away from Krell to something else, My speakers, they are all timers too🤣 . Martin Logan‘s Monolith from 1986 with newer panels though, And Wilson puppies.. They look like Laural and Hardy. They sit next to each other, and I love to switch between them to different kind of music. For some poor recordings, I have also subwoofer. I love Manolis for classical music. The sound stage is just incredible. For Jazz and some rock music there’s nothing like Puppy. Could be that Krell amplifier will get refurbished to original sound quality, but preamp I’m not gonna bother with it.

As I mentioned before I like the sound of audio research and never heard McIntosh, but for some reason, I like the look of it 🤷‍♂️ if it sounds as good as it looks, I will definitely consider it. Wow, that would be quite a jump. Well, years ago, I was much closer to new electronics high-end. Going to some electronics shows I met Jim Power’s from Martin Logan what a great guy that was unfortunately no longer with the company so everything is changing.  Now I just enjoy my music and I would really love from some of you gentleman to give me some advice. I don’t want to change the speakers that’s the bottom line. I have also good turntable. It’s a Linn sondek LP 12 so I would need to work around these things I hope for some good advice. I would really appreciate that. Thank you so much.