Grab the Taalo shield, and then crush the small force at the Umgah homeworld. Drones are easy pickings for most ships, you'll get a bit of bonus RU, and the Umgah will happily fork over a cool 1000 credits worth of biodata. That should keep you happy for a while... and if not, you can always hunt up those Rainbow Worlds...
you can easily find a list of bio-rich planets, but if you're going on the 'walkthrough' side, might as well just hit the rainbow planets on your exploration travels. I think visiting 6 is enough for everything you need from the Melnorme.
"You boldly enter our space! Approach this Dreadnought as though it were a recreation base and then play the dumb hominid? Who do you take us for, Captain... Spathi!?"