Keep in mind Organic weapons are also pretty weak (until the end of their tree at any rate), and so the Emissive Armour can ruin the day of any organic ship fairly easily (for example, the Lightning Ray only does 10-20 damage at medium range; even with a Large Mount, you will have a very tough time doing any damage against a ship equipped with this Armour). Their armour is much better, but I don't see so much of a difference with regular armour (well, it regenerates, but if you are lucky ships will get banged on and so there won't be much to regenerate after that. And if you aren't, the AI will attempt to scratch every single ship in the battle without actually destroying one).
Also keep in mind you can retrofit your ships, removing one or two turns of build time. You will need to keep a decent repair rate for this however, and you need to be fairly wealthy (a retrofit costs 20% more and you need to pay maintenance while retrofitting). Still, with fairly high construction bonuses (around 135%), you can easily build Battleships in three turns with a retrofit, provided you use armour instead of shielding (shields tend to bring the build time to four turns).
So having Organic may remove one more turn from the build time, but that implies you have the resources to build them that quickly and to maintain them. I had a very tough time using all my spaceyards with the design above, at least until the end game (where half the galaxy was virtually under my iron grip). High construction rates may appeal you because they allow to build colony ships more quickly (with a retrofit), but how much of an advantage it gives depends on your mileage.
