There's no real right or wrong answer about contact with the other civs. If its Monty, Alex and Genghis over there, we want to leave them as long as possible to fight amongst themselves, if its Mansu, Gandhi and Elizabeth, we'll have lost the game by the time they discover us. We'll only know what the right thing to do is after we know who they are, when its too late.
A GP would be good, as would a GS. Maybe employ both in London and leave it to Lady Luck. Pacifism would probably kill our fragile economy, unless we deleted alot of troops. We should be able to get 2-3 Great People relatively quickly.
If we do skip CS, a GS will bulb Compass, Optics and Astronomy.