This is a slightly experimental mod with an unusual story. It is not set inside the Half Life universe and there are some game mechanics which have been subtley altered. The pace starts out slow, and builds up gradually.
This mod is intended to be more of an adventure rather than a shooter. If you approach this mod as a pure shooter, then you will probably not enjoy it.
There are some intense action scenes, but most of these come later on, much of the earlier parts of the mod are focused on adventure and storytelling.
There are numerous cutscenes. I know how some people don't like cutscenes, so the majority of them collect together loosely to make the "introduction". There are a couple of short ones scattered around later, but they never really jerk you away from where you are standing. At any rate - once you have a weapon, the amount of scenes drops off dramatically and the game leaves you in control much more...