These are all valid points, but the only problem is that they've all been done. I could be wrong (in fact I dearly hope I'm wrong), but I think it safe to say that the horror genre for gaming is dead. Gamers have been exposed to every type of scare now, to the point where nothing is original anymore. Back in the days of Resident Evil, Silent Hill and Clock Tower, the concepts were new, the gameplay was new, the idea of scaring people through the form of games was new. Almost 10 years later it seems that every source of frightening material has been exhausted, and although companies try to pump out scary games, and even though some of them get close to succeeding in making us sleep with the lights on (Dead Space, Amnesia: The Dark Descent, the "Lost In Memories" DLC for RE5), nothing these days seems to emulate that quickening of our pulse and the desire to hide like the first time we met the Pyramid Head, or when zombie dogs came crashing through the window, or when some decrepit kid fell through the ceiling and stabbed us with over-sized garden shears when we thought we had found a good hiding place...
That being said, I'll still play horror type games that release in the future, and I still hope that one day some game company will get it right, because we're long overdue for a good scare.