I’ll give my two cents. I see the M-ATX you have already… I am using this and am VERY happy with it. I use the Fractal Node 804. Its a little larger, has dust filters, and room for SOOOO many fans you can run them super low and keep temps very low. It also has room for a VERY large CPU cooler, and room to expand disk wise. The back side has room for 8 3.5in. drives or twice as many 2.5in. drives if you use dual 2.5in to 3.5in adapters.
You can see it here.
And this is my build.