You'll be hard pressed to find a monitor with a better overall customer rating. About 90% 4 & 5 Egg rating. List of 23.6" LCD monitors Visit link @ NewEgg and choose the sort option: Best Rating (upper right)
You can try that sorting option in other categories too.
It's not easy to pin down the reason some monitors have issues but shipping damage is always a possibility.
Ask as many questions as you like.
It's true your original MB selection didnt have USB 3 or SATA 6Gb/s built in. If you ever found a need for those options you could get a add-on card for about $25
What you'd be giving up on the MSI 870 board is the 2nd PCI-e video card slot runs at x4 speed vs x8 on the MSI 790X-G45. Both run a single video card at x16. 790X-G45 runs 2 video cards at x16/x16 and 870A-G54 run CF @ x16/x4 (which isn't quite as bad as it probably sounds).
IMO the best reason to have USB 3 or SATA 6 options would be a fast external HDD (USB 3) or an internal hi-performance SSD (SATA 6).
That's not to say that USB2, e-Sata or SATA 3 is in any way bad or lacking good performance.