Yes, how it play, and the feeling of the game. the tense of the game, various feelings, various length...
As with most games, the 2p version is quicker and the focus is on limiting the maximum gain of your opponent.
Having "more powerful" pieces is more important than having more pieces, because you can effectively negate your opponent moves by placing more influence where he placed his pieces.
It reminds me a bit of 2p Agricola.