By default the game comes with 3 mods. Hard Mode (increases the cost of extra areas or something), everything unlocked, and infinite money.
So you can just use the latter 2 and build whatever you want. The game is pretty easy though, so I'd recommend atleast trying it out normally, you can basically get unlimited money by just building a small area and playing on max speed and letting the money flow in.
I don't know how it compares to Cities XXL personally but most people seem to think it's the best city builder since SC4. I think the only real downside to the game is difficulty, but personally I just play city builders to make cool cities rather than the challenge, so I don't care much about that.