While Fear is good compared to the likes of Quake 4, it is nothing compared to Half Life 2. Fear had a creepyness to it that did make the game better, until you realized how predictable it was. You could always tell when something would happen in Fear. Also, you fight only a very small variety of enemies throughout the game, and can complete the game using the same tactic, over and over.
Hide behind corner, activate slowmo, snipe a few guys, go back behind corner, wait for slowmo to charge up, repeat.
Half Life 2, on the other hand, has comparable graphics to Fear, while at the same time running three to four times as well. Half Life 2 is also a much longer game than Fear, and offers a large variety of gameplay. You get your run and gun levels, your sneaky behind the corner combat, long driving sections, and all kinds of enemies ranging from little alien things to big alien things to enemy aircraft, to an entire assortment of enemy infantry. Half Life 2 had some memorable music in it, and the game just seemed to present a more believable world than Fear.