Bongo?

You should look into LACP again: It will NOT add the 2 gigabits into 1 adapter, but into 2 streams. when you move a file, LACP will still only use 1 adapter. (as will load balancing)

Load balancing is meant to balance between two LAN. Synology can make this work with any switch or router.Link aggregation is something that depends on a switch. Each switch is different and comes with its own config pannel and way of doing it.I hope this helps.