Ok yeah I see what you mean the cpu maxxes with the tcp but not udp. I thought was some sort of overhead issues.
As for my script put the same bonding on two router boards and connect port 4 and 5 together or whatever ones you want. Rember the ports you use cant be in a bridge you add the bonding port to the bridge.
R name="bonding1" mtu=1500 mac-address=4C:5E:0C:6D:45:3D arp=enabled
slaves=ether4,ether5 mode=balance-rr primary=none link-monitoring=mii
arp-interval=100ms arp-ip-targets="" mii-interval=100ms down-delay=0ms
up-delay=0ms lacp-rate=30secs transmit-hash-policy=layer-2
Hope that helpes