If you're experienced with New Leaf, you should be able to find your way around City Folk very well. If you're concerned about grass deterioration, that definitely is a problem in this game. If you want to prevent it, try to create paths and walk on those as much as possible.
When donating to the town fund, make sure to do it all at once. If your donation exceeds the amount of whatever you are trying to build, that money will be for absolutely nothing. The extra bridge is 200,000 Bells, the fountain 400,000 Bells, and the lighthouse/windmill is 1,000,000 Bells. They are obtained in that order.
Also, this is something that personally interests me, there are a number of rare landmarks your town can randomly have. My favorite is when the rivers split in your town's bottom half, forming an island in the middle. This can also allow your town to have 4 bridges. There are also canyons which can form in the right side of your town, and the cliff ramps can have some rare and interesting shapes. If this stuff sounds interesting to you, I recommend resetting your town until you find a nice layout. From my experience an island takes about 10 tries to spawn, and canyons are fairly common.
I hope you enjoy your time in City Folk. It doesn't have nearly as many features as New Leaf, but it's still a good game with some merits of its own.