XCom does many things pretty good, but nothing great.
Graphics are meh. Old and not impressive. The music....by God, could the developers have spent a few bucks to get some more music? There are one or two songs that play over and over again, and I finally had to basically mute the music.
The turn based strategy is the highlight of the game, and though not too challenging on normal (once you get used to it) you can amp it up one or two more difficulty levels. Even if you lose a squad member and want to start over, just save along the way and you will find the enemy positions and be able to compensate from your savepoint.
The base building is almost nonexistent, but there is a good research tree to improving your weapons and armor. I think this game could have been great with superior graphics and music, a better storyline, and some more character development. As it stands, it is still pretty good.