Heya!
I've got now about 180 hours of playtime with GC3 and tried many different strategies. First diplomatic, then influental and after that economic. But from all things I tried full manufacturing was by far the most powerful playstyle in any terms.
I mean.. You need some science? Use da hammers!
Influence? - Produce the heck out of it!
What about money? - Stop! Hammer time!
I looove this game! - But I'm not sure if this is.. uhm.. balanced? 
Especially the influence-production-increase is by far too strong in my opinion. I mean.. it's quite cool to gain an influental victory after just 25 turns starting the cultural festival but this just makes things too easy I think.
Anyone got the same impression?
So far o/