I agree that a desktop is the better bang for the buck, unless you really want the portability. The 17" screen looks good, but I think you would be happier with an SSD with at least 256GB, and optimally 512GB if you play other games besides Civ. With today's games its amazing how fast disk space disappears.
Also, even though it might not always be possible, if you're going to buy a laptop it helps to try it out in person before buying. Trackpads/keyboards vary between laptops and the only way to know if they suit you is to test them out.