Kigi is that rare blend of art and game. Using the brush strokes and decorations provided by the cards in the game you not only 'create art' as a game play goal, but you create actual art right there on the table in front of you. The tree you create is unique to you and to that moment of play. Goals drive the direction of your creation, but you decide how and when to complete those goals and the resulting tree you bring to life is suitable for framing.
Daniel Solis' art and game design are, as is so often the case with him, brilliant. He's consistently good at taking very basic elements and creating fun and interesting game play and mechanics with them. Kigi is no exception and the fact that the strategic decisions are simple yet meaningful helped make Kigi one of the more interesting 'light' games I've played recently. Sure, you can concentrate on just painting your own tree, but would it be worth stopping that long enough to interfere with the paintings of your competitors? Since everything scores in chains, it might be vital to your success to do so.
Finally, while I myself enjoyed Kigi quite a bit, it hit an even more important marker. My parents, who are notoriously hard to engage in boardgames and cards games that don't look like traditional roll and move or pinochle, found Kigi to be to their liking and enjoyable to play with the entire family. The fact that they requested another game of it two days later speaks volumes once you realize they usually never make it past the first turn of most other games.
Go. Buy Kigi. It's worth the price.