There are no winners in the "I want to air cool this thing" category in regards to the X570 / AM4 ITX / M-DTX motherboard offerings...
I will probably go for the Asrock offering, the Thunderbolt is quite useful to me, at least I could add 10GbE to it. I think such high speed external bus is one of the most optimal usage of the PCIe lanes for as sff PC.I think unless you are using a 3800x or 3900x we are going to be better off waiting for the B550.
If you aren't running a 12 or 16 core or wanting to RAID Gen 4 NVME, do you really need more than a MSI B450i? I'm struggling with that myselfI think unless you are using a 3800x or 3900x we are going to be better off waiting for the B550.