I played several games with the Yor trying different new research strategies with the yor while using the governor's instead of planet wheel, but regularly find myself crippled with inadequate population even though my social manufacturing output is significantly higher than everyone else's (often a baffling last place population). I think that with the shift from colony by colony to empire with colony governors yor either need to have the cost of assembly/fast assembly lowered or the resulting output of SyntheticPopulation increased so that it can at least keep pace with breeders without needing to devote all worlds to assembly nearly every turn.  

spending ~15-20+ turns on a new colony with 3mil yor to get 2 mil from assembly doesn't even break even with the flat .1 rate breeders get in GalCiv3GlobalDefs' GlobalColonyMods before any tech improvements to improve that .1/turn.  The numbers get even worse when a farm or hospital piles on their growth multipliers.  While I'm not sure how much assembly/fast asse,mbly should be altered, I think it very much needs to be altered in 1.3 (maybe 3-4 SyntheticPopulation with assembly and  6-8 SyntheticPopulation fast assembly?)  As it is now, I had trouble keeping up with  the output needed for seed seed constructor (build) from a fully built up iconia with 4x economic starbases  improving the mfg collectives further at the current 2 & 4... Prior to 1.3 I could churn out seed seed seed seedand continually grow the population of iconia without difficulty