All of boards seems OK but I think it is not the best choice for your new NAS.
The price of these boards should be higher than $200 and the E3 v5 CPU should be more expensive and has more requirement for heat radiation.
In my practice, I used DELL R520 servers(2*L5520, 8G DDR3 REG, 6*2T HDD, 2*10G LAN) for ESXi matrix (more than 500 VMs) and use DIY NAS (G2120T, 4G DDR3, 4*1G LAN) for my private lab and decoding via Synology Video Center (2K source). So, a newest CPU (E3 v5) or fastest memory (DDR4) has no relationship with customer experience (or less obvious).
If your budget is more abundant, a better chassis and quiet power may be more important than a newer CPU or faster memory.