There isn't anything better than learning the past of the greatest soldier to ever live, the Messiah of Modern Day war, so too speak. I think I built up that determination through hours and hours of Final Fantasy.
You should give MGS 4 another try, I tried it on Big Boss hard and you don't get a gun to start, just a stun knife, the enemy soldiers are really hard to kill and a head shot is almost impossible, don't even get me started on the Geckos. The enemy AI seems to have been increased, they won't just rush blindly in to a room anymore, they will through a grenade or split up and go in from the front and back, checking all of the escape routes if you are not there and pacing the room several times. It does get annoying, as you can't get away from them.