Welcome! I'm late to this party.
I waited 3 years to build my first NCASE M1 , with it sitting in my closet the whole time. Currently, I have a CCD MI-6 sitting on a bookshelf waiting for my next build.
NCASE M1 can be a bit tricky to keep quiet. The aluminum is classic Lian Li which means it's sensitive to vibration. It can hum if you're not careful. Additionally, they allow noise out 3 of the 4 sides, plus the top and bottom.
How much are willing to give up to make the system quiet? I used to be a member of Silent PC Review so I literally took a dremal to Lian Lis back in the early 2000s to add exhaust fans, and was part of the Antec P180 launch buyers. My current main rig is a Cerberus X with an NZXT X62 with Noctua Fans, all SSD, custom fan profiles, solid side panels, sound proofing foam, and a giant mistake in the form of a Founders Edition RTX 2080 that's obnoxiously loud. I'll be giving that to the wifey when the 3080 comes out.
Can you accept high temps? How flexable is your system placement? Does coil whine bother you?
A super quiet rig might consist of a Platinum Corsair SFX 600, Noctua C14, Noctua 92mm exhaust. The GPU would be a carefully selected 2.5 to 3 slot solution that doesn't even spin up till 50C. Use a balanced CPU option like an R5-3600. To top this, you would undervolt everything, and use custom fan control rather than the BIOS. Only SSDs. If you allow the system to run a bit warm, you could then have an essentially silent system at idle or light CPU load.
A more moderate solution might be a Thermalright Silver Arrow 130 combined with a the graphics card and PSU I mentioned, and tuned in the bios. Alternately, you could also try a 240mm RAD with Noctua A12s set for silent running.