I find that the first paragraph for the Assimilation puzzle very ironic. When playing the previous game to this, I took some word or an idea and went to google to find a word that might fit the answer. After many trial and error, I would eventually find an answer and feel all the strain on my brain being rushed out and leaving me feel refreshed, it was kind of rewarding.
This game is no different. It has challenging puzzles that takes time to solve and it gives the same rewarding sensation. But as I sit here for the last five hours with the Assimilation puzzle in front of me, I began to notice at how surprisingly true that last sentience is.
These puzzles are definitely more challenging and (judging from what I've noticed and your theme for the game) elaborate.