Honestly, if you look at it, the creature creator trial
That simply because you had limited parts in the creature trial and pretty much had to work with those.
We are talking about the actual science part of the game, such as placing legs in an odd place would make the creature stumble and walk different, making certain parts bigger would actually effect weight and make it lean, etc. All of this was taken out because Chris thought it'd be too complicated.
ecosystem dynamics were removed
physical properties of creatures no longer make a difference
- amount of legs don't make much of a difference, it's all based on stats and parts now
- they don't shift under their own weight
- placement of parts does not matter (Having spikes on your back would protect you from being bitten when running away)
evolution, or gaining a bigger brain so to say, being optional was removed
the inability to travel beyond light speed was removed
And I'm sure much more was removed, that isn't described in that thread.