Amp question with size constraints


I am in the process of looking to upgrade my amplifier (presently a Rega Brio R), but I am faced with size constraints: given the built-ins I have, I cannot really go much beyond 13 inches in depth. The trouble of course is that better amps tend to be larger in size. 

To add another wrinkle, I primarily listen to vinyl (via custom Linn Sondek TT w/ MC cartridge and Fyne floorstanders). I've seen positive reviews of smaller Cambridge and NAD integrated amps, but they tend to focus on the digital side of things. What I'm wondering is whether an integrated amp with my size constraints would work well with my setup for vinyl, or alternatively if there is a good power amp within that scale that I could just pair with a decent phono preamp. 

I am not married to any particular approach but am not really sure which way to go at this point. Help me, Obi-Wan, etc.

polanskyd
Post removed 

Second Class D either Purifi or GAN. I have a Nord Purifi and it completely knocked my socks off after many years of tube and SS gigantuan amps.

I had a depth issue with the massive Denon AVRX8500. I wasn't going to let that stop me. So I put a suitable size extension underneath it to extend the depth. It's stable, and it just sticks out a bit. Actually about 2". It took no time for it to look ok.

Many thanks for all the replies. A couple points: 

1. I am not a bot

2. I am replacing an integrated amp so I am happy to go either with superior integrated amp, or a pre/power setup, provided they match the space constraints.

3. The GAN option sounds very promising.

4. I had assumed that Class Ds would be a step down though that increasingly seems to be a prejudice.

5. Speaking of Class Ds, one of my local dealers is pushing the Cambridge Evo 150, which has streaming capabilities (which would be a plus for my wife). Does anyone have any insight as to whether that would be a good product along with a phono preamp?