The Elathen, Zerg, and Tyranids beat you to it. Even though it's a bit common in sci-fi, I'd see no problem with it for the expansion.

I think organic ships look good in Genesis Rising  

The game was yes. Still the idea of the ships and how you could harvest DNA from dead ships, even the enemy ones, to preform upgrades was interesting.

Genesis Rising was irritatingly micromanageish to the point of depression in my opinion

I totally agree, but the Iconah's mothership is realy good especialy when you mutate it.

Old and unoriginal to use organic ships.
New and trendy to use metallic ships.
Old and unoriginal to mix the two.

You forgot the Yuuzhan Vong.

they really have been done pretty much everywhere, but I have no argument with a decently executed addition.

Well, the post reads "a alien race wich uses organic(biological,living)ships". And of course it could be cliche, but yes, it depends on how Ironclad/Modder X executes it.
And the concept of the TEC is more a cliché then biological ships to me.

Yeah, I'd not want an organic ship. It'd be useful for certain interior parts as organics both typically are far more complex and smaller than mechanical equivalents, and they could heal, but have you seen what a bullet does to flesh? Seriously, I'll stick with metal.

Plus there's the whole 'organic' part. Think 'War of the Worlds'. When someone figures out a disease and shoots it into your ship, you've pretty much lost the whole war.

Good execution makes an overused topic seem quite original.

Metallic ships have been used since man first thought of venturing into space in a vehicle.
And when has someone come up with a cybernetic ship? Is there a major sci-fi story I missed somewhere?

Actually, organic ships are quite feasible. Think of how hard it is to crush, say, a cockroach. Now, make this cockroach the size of the Empire State Building and have a shell that is about forty times denser. Think it's going to be very easy to break through that thing?
Let's not forget that an organic ship would be able to recover in combat fairly fast compared to a ship made of inorganic parts; the damaged components would fix themselves without need for assistance, thus meaning there'd be not much stopping the ship from repairing itself.
A highly adaptive ship would also be much more resilient. It'd be able to identify the incoming threat and prepare the threatened section for impact. It might even be able to make a hole in itself so the projectile would merely pass through.
And metal is fairly capable of igniting. Having a bunch of plasma shots and laser strikes flying around just makes it seem like a tree in a burning forest.

Plasma doesn't care what material it's hitting, it's still going to burn pretty badly. And autocannon rounds certainly aren't going to be affected very much either. Lasers might be adversely affected by highly reflective materials, but not much else.

You see, this is the mentality people need to get off of. Organic ships would most likely not be flying fleshbags. They'd likely be akin to insects in having an exoskeleton as opposed to soft flesh.

Just like the viruses would be able to adapt, the ships would be able to adapt. If you wasted all of your money on this virus technology, you'd likely have a stockpile of virus bombs that'd be rendered useless in the first few weeks of combat. Build a new bomb, one more adaptation for the enemy. It basically becomes the weapons VS armor race all over again.
Now, let's factor in the distance and hostility to exposed organics that space has. You can't simply fire off one weapon and hope it hits everything.
Although, that would be a neat ability for a ship; it fires off the virus bomb which does damage over time to an organic target.

Maybe it would be a good idea to just add an enormaous organic plane eater. The planet would be consumed. Maybe even to devover a entire sun?        

Uranium, I'll have to note that there's no way you can establish a fully functional tax base on a planet that your TEC bases have nuked to oblivion half an hour ago either. Yes, the justifications are weak, but they're not a lot weaker than anything else that has to be compromised on in order to make the game enjoyable.

I don't particularly want organic ships in the expansion pack either, but not because they don't fit with scientific protocol. Sins violates that in plenty of areas in its current incarnation anyway so I don't lend a lot of weight to it.

-- Retro

I meant PLANET eater.

Fair play to that