Turns out part of the speed problem was letting the non-used drives fall asleep.
More importantly….I’ve never heard of a RAID 5. So, from reading about it, it seems like that’s my best bet: if I don’t plan on backing up the 4 drives worth of exported files….but I don’t want a RAID 0 cause I worry about one drive getting hurt….I can do a RAID 5 so that even if one drives dies, I can easily replace it and have my information restored? It seems almost miraculous as I’m reading about it.