So yeah, bigger is better, imho. For cooling, low noise, and aesthetics.
I've lived both now, Corsair 250D for years in MITX and now Meshify C in Mid Tower. The H1 solves a lot of problems I had with ITX; most of the cable routing is basically done for you, cooler and PSU are already there. It's probably the easiest desktop PC build you can imagine.
The problems in my exp come later, and depend a lot on your home situation. ITX boxes like that pump heat out like a smokestack. Noise - while not annoying - is clearly audible and requires more maintenance for dust and potentially repasting. And depending on where you point it there is literally a dual slot GPU fan pointed at your face. So if you're in a warm environment...that sucks. Meanwhile, my 6 fan Meshify doesn't even make an audible sound when it turns on. (But it's big enough to go under the desk...). Still, they both have their place and the thought of a no-nonsense build like the H1 is appealing.
Favourite of mine has long been gamersnexus Steve, the level of component testing and relative efficiency of his videos makes it an easy tech channel to follow. Everything I bought based on his recommendations have exactly matched his test results and build quality impressions. Honesty is so refreshing.
With Steve it's not so much honesty as it is scientific rigour. Gamers Nexus is thorough. They think through the test methodology really hard and at times are pure investigative journalists. Linus and LTT are also entertaining and helpful, but not so much a rigour channel as a +/- stop. Sometimes, you just need the "should I buy it?" but when it comes to CPU, GPU, Case comparisons? The rigour *really* helps. They basically browbeat the case industry into mesh.
There is a whole spectrum to this, honestly - LTT on being entertaining and key points, GN on rigor and detail - so depending on what you find helpful there is a mix of useful channels. Hardware Unboxed, for example, sometimes gives the appearance of "here's a nice table with 5 motherboards", but they were instrumental in taking MSi to task over their VRMs and even recently
crushed Tom's Hardware for their lackluster test methodology.
This is what I'm really considering upgrading to sooner than later. The question is, should I get this now or wait until the 4th Gen Ryzen CPUs come out in the summer? I call it my blackout build.
pcpartpicker.com
Hard to say if summer is really happening for Ryzen 4000 (some of the above YTs are doubtful of that date) but my opinion is basically that if you are set on R4000 but want to build now, you want the Ryzen 3600, which is just absurdly cheap. If you want to forget R4000 and build now, the 3700X is a good processor. But microcenter/amazon have recently been selling the 3900x for around $400 also, if you have access to either.
The build itself looks fine, though generally I would avoid MSI X570 boards until they resolve their VRM problems. MSI was the gold standard for B450 but screwed up on X570. Maybe that particular board is okay - I would look online for info - but if not that one there are plenty of other good X570 boards for that much or less from Gigabyte (Aorus), Asus (ROG), etc.