The only thing I don't like about Sci is that the last bonus comes quite late in the game. Often too late to be relevant, especially in multiplayer. I'd also like to see double production speed for Observatories - I think the traits were originally designed to give 1-2 bonuses AND double production for a couple of buildings. So they can function in completely different ways AND give double production speed. That's how I see it.
Btw, I'm playing a singleplayer game as Adriaen van der Donck at the moment, focusing on scientists and ran out of Great Scientist names in the 17th century (there are some more Sci civs in the game).
Two comments about wonders:
I don't like
Petra - I would build it only to get more or specific Great Person points early, but it gives Statesman points by default, so you will pollute your GP farm, which makes the wonder rather pointless if you don't farm Great Statesmen. I would rather have it not give any GPP itself.
The
Great Bath is a pretty good wonder, but suffers from two problems. First, it directly competes with strategy defining wonders (Pyramids, GLighthouse, Sphinx, GWall and to a lesser extent Stonehenge and the Oracle). Second, the AI seems very keen on the Great Bath and usually builds it quite early, turn 100-150. Unfortunately this means that I am never going to build it.

Could it get pushed back (or forth, depending on your point of view) on the timeline, becoming available with, say, Mathematics?
The Sphinx is brilliant btw and very well balanced!