I had a dream about the Sower on ES2. They were designed as a "symbiotic" kind of faction, focused on improvements and colonization. Their affinity, Planet Shapers, gave the ability to add and anomaly "planet hub", that gave a second population row of 3 pop per planet and only sowers could live there; when in the secondary row they were "virtuals" giving the system a +1% FIDSI per virtual sower, and while "concrete" they used the normal population row, but gave only +1 Ind bonus (could be dragged in between the rows). Any planet could be used to create a hub, even non colonizable or not colonzed (but required an outpost/colony in the system). The virtual sowers did not get any effect from planet or improvement happiness (they weren't count in system approval).

The thing is, when a virtual row was completed the virtual hub could be upgraded, between cybernetic-type, organic-type or neutral focus, adding a bonus per concrete (sower or not) population. A "cybernetic" focus improved industry and science, an "organic" food and dust and the "neutral" gave influence and happiness. Each improvement had 3 tiers, each tier giving +1 extra population to the virtual row and +1 to the focus bonus. Any focus could be changed as improvement (high industry cost). Terran and other T1 Planets that have a maxed hub could be shaped into a planet-type called "paradise" with the highest FIDSI stats from normal planets and a +5 aproval, but unable to add a focus to the hub.

An interesting trait in my dream was "hivemind politics", making the original population on empire always vote for the player supported party.

Weird dream, uh.

You must be fascinated with Sowers.

I tried to make them as a custom race. Riftborn visuals and planet brokers but it's just not the same :( 

The riftborn whole another dimension race ruins my robot race.  In every 4x i play i take on the robotic race.

Riftborn aren't technically robots... they're extra-dimensional beings. They just use these robot looking bodies to be able to function withing the ES universe.

I never played ES1, so I draw my information solely from the Wiki. The Sowers and the Automatons seem to be some very interesting factions. Wouldn't mind it, if they get added one day. Thus, I like your ideas about the Sowers and the additional pop row and the focus options coming with it. Also, I would fix the focus once it was set. Otherwise it sound a bit too powerful.