Ok, I'm going to experiment a bit with the link aggregation.
Had a 500GB (7200 RPM) test hard drive in my unit (while waiting for two WD Red 3TB drives to arrive). While doing a backup from my computer to the NAS I was getting 9% network utilization (Windows resource monitor)....and backing my system drive as a 260GB image (sector) was agonizingly slow.
My two WD drives have arrived and are installed.
I was out of ethernet ports (Dlink DIR-655 4 port + Dlink 5 port switch) so replaced the 5 port with an 8 port switch and thus now have LAN 1 and LAN 2 cables running into the NAS.
Will do some reading and try to figure out what is the best choice for joining the ports to improve performance.
This document
http://www.mjmwired.net/kernel/Documentation/networking/bonding.txt seems to offer the most useful information on the way to "Maximum Throughput", in section 12....but I've read it twice and it hasn't sunk in yet...hoping others will take a look at this and offer suggestions..!!