if_only_we_were said:Hmm. At this point I must ask what level you are playing at.
Monarch and Babylonian.
Is this a serious question? Well, of the top of my head, I would say - to run at 100% science, to rush buildings, to preform espionage, to bride other civs into war, or keep them sweet. I am sure you could think of others if you tried.
Of course I'm serious. Game have "4 turn limit" by default. So if 60-80% is enough to reach it there is no need to run at 100%.
If you are not at war, it is enough to spend 10-20% on entrtainment to keep people happy. Only thing you need is to obtain at least 5-6 Luxury resources.
Bribing and gifting are very un-productive for me. But I have to admit: never had the Diplomatic victory.