Suggestion on the initial setup – something that was hammered into me a long time ago – “KISS” = “Keep it simple”.
The network is probably not going to be the choke point, the choke points will almost inevitably be the disk I/O.
My experience has been that teaming is a great idea in the lab at the switch and NIC vendors, but in real use, it just adds a point of failure that always seems to bite me in the rear at the worst time (like late May, early April). Every time I’ve tried to team nics in the past, I’ve had problems every 6 months to a year with the software failing on either the server, or the switch.
My suggestion would be: Your GB network idea is a good one, start with it, get numbers on your throughput end to end, then try teaming the nics and see if it changes the numbers enough to be worth the effort.