My 2 choices will be Asus and MSI.
I would and have used MSI in prior builds but,
Asus has a couple of issues. One of which is a huge red flag with them mounting a capacitor in reverse polarity and killing boards / starting puffs of
smoke.
MSI was decent to deal with in building but, in the ADL world at launch didn't have what I was looking for. I didn't have any issues with them but, they just didn't fit the needs for all of the drives + the other perks the ASR offered.
A lot of boards these days are forcing the issue when it comes to SATA ports and using offloading bridge chips or knocking off available ports when you use more than a single M2 slot. The way around it though is to just add an HBA to the mix on one of the slots to get another 4-8 ports to plug in drives. I have to contend with this as well running 5 drives + NVME's on the same board.
As for cases I use Fractal Design for the space they offer in compact solutions. In a prior build I used a Node 804 which holds 8 drives by design and has a small foot print and the drives are isolated from the MOBO to keep cooling optimal for either side of the case. For the ADL build there wasn't any mATX boards so, had to bump it to a mid tower and went with the Meshify 2 which holds 13 drives IIRC but, I double spaced them in the rack to provide better air flow since they're not compartmentalized like the 804.
It sounds like we're both geared for the same setups though other than the OS / MOBO. I think the MSI I used was a Pro 4 if that helps.