It could still be creativity-based. Creativity might simply increase the chance that otherwise unaccessible tech breakthroughs happen. The +25% just indicates a positive modifier the game applies when checking to see if a breakthrough occurs.
Since percent modifiers are applied in many different ways in this game, that +25% could be very significant or it could be very miniscule. Or anywhere in between. If we assume, though, that it works largely as the creativity pick worked in the first GalCiv, this seems to be the end result:
If you pick creativity, then in a game of moderate length (say, over a few hundred turns) you are likely to have 1 and maybe 2 creative tech breakthroughs like "hyperwarp" (or whatever it's called). If you do not pick creativity, you might experience such a breakthrough anyway - in my experience, probably 1 in 10 games.
Here's something else to consider, though: does a "creativity"-driven breakthrough grant a benefit to all races? If it does, then just having the Altarians (with their +30% creativity or whatever it is) in the game makes a breakthrough pretty likely, even if you don't use the pick. And you'd still get the benefit of the breakthrough. It's hard to know if picking creativity is even worth it if you might well get the benefit without spending the point at the creation stage.
The creativity pick seems to illustrate a general problem with the documentation of this game: too often, the player has to make fairly uninformed choices. Now, one thing I like about the game is that even without specific documentation you can make a _somewhat_ informed choice based on the in-game information. For example: Creativity gives +25%, but only costs 1 point. That suggests that the advantage it gives is not very crucial. The problem, though, is when you want to see what's under the hood (i.e., ask something like "what, actually, does creativity _do_? What are the numbers?") there isn't really one place to go to find the answer. Yet.
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