A very good vision on the 'perfect' semi-organic lifeform.
Probably the biggest potential downfall of this race is its inability to continue if the central infrastructure is somehow taken out of the picture. Unable to reproduce without it, tied psychologically to it, the centralized nature might be an impediment to it taking over. If the sun went crazy and EMP'd the hell out of the solar system, humanity might eventually recover. These guys would not.
This comment of mine is somewhat ironic - I had the Zoimorphisits School of Magic which is not much less of a mouthful, but shares similar bio-modding, with magic of course.
Genomorphing? - This is already in use in a few places.
Clade is a word I literally learned yesterday when looking at wikipedia about how closely related puffins are to penguins (they are both birds, that's it..). It a nice technical word, but hardly common.
Biogenesis? - Creation of new types of life from other living things.
I would guess there is a safer sea-route that while longer is 'cheaper' in less lost expeditions.
This place could come under new focus if the sea route became untenable due to a failed alliance, new powerful enemies and the like. The PCs could be contracted to clear a fixed length of road, or paid by the mile.