well, i'll try to make a summary on what this traits generally do. i understand my attempt is doomed to be unsuccessful, but still i'll try.
1. Organised.
Generally it allows you to REx faster, and more effectively, either through settling or warmongering. Its uses are especially strong and evident early-game, although it gives forge-price factories, facilitating industrialisation.
2. Financial.
This merely allows you to produce more beakers, both by directly gaining more commerce for science and providing the opportunity to keep slider higher. It also indirectly facilitates expansion. It provides all-game-time gains.
3. Spiritual.
It saves you from either several turns of anarchy or nesessity to wait with civics changes before you can expend GP's for GA. Gains are most strong mid-game and late game, but however it must be taken into consideration that you can emulate this trait by beelining Radio and building CR (for the cost of NOT beelining military techs, however)
Spi also gives you free diplomatic points with other civs for accepting their SR's and FC's.
4.Protective.
Pro enhances espionage economy and makes your city defences much stronger and your gunpowder units more versatile. It's gains are all-game-long, but somewhat situational (as it seems to me). It is especially strong when you actually run EE.
5. Aggressive
it makes your early-to mid game armies much stronger and axe-sword rush much earlier and easier.
Gunpowder units benefit from it, too, so, taking into account this and cheap docks, it provides also some all-game-long benefits.
6.Philosophical
It allows you to beeline selected techs surprisingly fast, providing you monopoly on key techs and thus allowing to have superior military or build selected wonders when it's necessary. Cheap universities lead to fast oxford, thus giving more beakers. beeline is effective through all first half-game and unis+oxford have the greatest impact in mid-game, IMHO.
7. Imperialistic
It provides early benefit by cheaper settlers (if you hammer-build them), allowing to grab more land (when not boxed or isolated), or grab your faster (when boxed or isolated). Double GG emergence is good forever, but minor.
8. Creative
It grants early-game benefits, allowing you to place your cities optimally, granting them +20% defence bonus (same as CG1 promotion). It allows your cities (pre-CS) to produce research faster and get GS faster.
9. Charismatic.
I'd say it gives you early-game benefits,too,
it gives +2 (with monument) early happines, allowing you to either whip 2 more times or grow 2more pop. It also makes easier to get S-medics and CR3 units.
10. Expansive
It provides early game benefit by shaving several turns of workers production (in case you hammer build workers, too) and 1pop-whippable granary. harbour is icing, imho.
It facilitates industrialization too, with that +2 health.
11. Bananas
Bananas allow you to get selected wonder more easily (1 per era is pretty guarantied, IMHO)
And gives you cheap forges, which are early, expensive, needed almost everywhere, and are only buildings to allow engineer. all-game-long gains, but the strongest early-game, when you want wonders without tech lead, i think.
So after much thinking, i'd like to withdraw my vote and keep it to myself. All traits are great, as it seems. I have my favourites, but definitely cannot pick one i would consider the worst.