Do not watch people's gameplay. Play it yourself. If you're not really into complexity, you can approach it like a run and gun, at some expense. Or you can go stealth. Or whatever.
The training level and early stages are fairly boring, but stick with it. The story seems VERY boring at the start and you're thinking "oh, this is just another "USA is dominate" plot", but after the Airfield mission the story REALLY picks up. After that, there's just so much intrigue, so much tension, and the game really comes to life as one of the best things ever. If you've already spoiled the story though, I don't think it's worth getting. The AI in the game is pretty bad, even for it's time, and the combat is also kind of unbalanced. GEP gun sniper rifle dragon tooth sword regen run speed and ballistic protection mods, if you know what I mean. Skills are interesting but there are only 2 out of 9 worth bringing to Master level, one of those is pretty dubious, and some of them aren't even worth bringing up to advanced level.
tl;dr
If you don't know the story, get the game, sit through the first few fairly dull missions then finish Airfield and go "omg wtf" for the next 15 hours.