Machi Koro is a visually cute city building game. Partner and I only play with The Harbor expansion added in, so keep in mind those will be the mechanics I'm describing. I wouldn't call Machi a set matching or deck building game, although aspects of some mechanics remind me of those game types. The way the game works is there are four types of building cards which give you money if you roll the number to activate it: green (gives you money on your turn only), blue (money on anyone's turn), red (take money from other people on not-your-turn), and purple (unique cards). You start rolling one die and with two cards covering numbers 1, 2, and 3. You have a market of other buildings you can purchase and a set number of achievement buildings to build. The market is created by drawing from a shuffled deck of all the buildings until there are ten unique buildings in the market. If you draw a duplicate, stack it on top of the first one and keep drawing. The winner of the game is the person who builds all their achievement buildings first.
I like what the expansion did to building the market of buildings to purchase. In the main game, you had a set block of buildings available which covered the numerical range. You could fairly easily build a city that statistically speaking ought to net you money every or every other turn. With the expansion, the market becomes luck of the draw and there's a lot more variance from game to game. For instance, the last game we played there were no four or seven buildings (in case you're wondering how you get seven on one die, one of the achievement buildings allows you to roll one or two dice). It can be frustrating if you're on the wrong end of grabbing rare buildings you need to fill in numbers gaps. But boy is it pretty if you can pull off having three buildings active on one die roll, snagging you 33 money (in a game where decent haul for one roll is 3-8).
So, Machi Koro and The Harbor expansion. I heartily recommend them. It's an easy game to pick up and learn and enough depth for repeat play. Also, and this isn't something I see very often, it plays well with 2 or 5 players as it does with 3-4. Most games tend to break down at the ends of the range of players they support. Machi is still fun at the ends.