Usually, I shoot for any victory by the year 2350. Depending on map size, you could easily get an economic before 2200, if you do a free market and bee-line to planetary economics. Same thing with a conquer victory. If you're on a tiny map with no islands, a couple particle impactors and rovers, and you can usually win by 2150.
However, in my opinion, it is not the speed, or even the score on the game that matters, it is the quality. The game somewhat gives you a figure on this with the 'Alpha Centauri Rating' or something like that and gives you a percent. For the average player, a rating over 100% shows that the game wasn't just one by playing momentum style on a tiny map. A good number is 200%, although that is not at all considered great, more or less just simply average.
As for a Transcend victory on Transcend, if you can win between 2300 and 2350, you're timing will be decent, acceptable, and you score will be pretty high too.
And as for SE with the UoP, I would suggest Demo/Market/Knowledge/Cyber. If you don't like free market, substitute it in with a planned economy. While +2 effic may be nice with a green, on Transcend, you're going to run into beauracracy anyway, and I find +1 industry and +2 growth more helpful than capturing a couple of mindworms...