It is strange that stealth has had very little changed in all their Fallout and Tes games back to at least Oblivion. They made huge changes to combat and magic but the stealth has for all practical purposes stayed the same.
As a mod creator I love how the dev designed the components of the system. As a player I am just not as big of a fan of how they implement their system.
The system they made is simple an logical and includes all the conditions you would want such as light level, sound, movement, and naturally skill. And it is open enough to mod easily.
In my mods I fine tune the conditions so that NPC will spot you easily if you are moving or turning or attacking. And I put a very high degree of importance on distance and light level even over skill.
Doing this made the system that would allow the 100 skill sneak to stand in front of a victim as if they were invisible as long as they did not move and as long as you were not in H2H range. You had to wait for the victim to turn away from you (not looking in your direction) before you could attack or move to another positions.
This made the existing mechanic much more believable and more fun as it included player involvement and not just raw actor skill. The player need not have god like skill they just had to make logical choices to "win" with a super high level sneak skill actor.
I hate doing stealth in other games. After about 2006 I never again buy any stealth based games (er except assassin as I wanted to try the cool looking combat but I stopped playing that after only 15 minutes because of the very bad controls). But I love sneaking in TES and fallout using a modified version of their systems.