You have something basic that works. I was a little bit confused about the money. I didn't know I needed a bank to get a loan. Also, when I accidentally took out the loan, it was too little, so I had to restart the game.
Another thing is that I sometimes miss-click when trying to use the road connection button. You could consider making a connection tool instead. For example, you could drag a line from point A to point B and then ask, "Do you want to connect these?" Or, you could show the price in a small box so you can see how much it will cost. If you don't have enough money, it simply won't let you connect them.
overall you have something here.