I too found DX2 more "deep" than the first in terms of it's accesibility to various playstyles. I noticed more routes to take within levels, more variety in the uses of the various tools available, and a greater sense of being able to define your purpose in the storyline. I did however miss many of the finer details found in DX1. The ammo, the level size, the lockpicks, blah, blah, blah, etc.
Basically while DX2 improves on the strategic aspects, it glosses over many of the more common tactical aspects of DX1 (And many other games for that matter) which most gamers have come to expect from the genre. Jesus-in-a-box would have had achieved excellence in both aspects, and attained the expectations of every gamer.
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