Thanks _Vic_
I didn't mind DOS2 stealth, not saying it was great but could be built upon to make it better. The fireworks type distraction you mentioned sounds really good.
In DOS2 you could 'turn off' light sources, being able to change the environment to change your sneak options also gives good role play options. In the Thief game you could shoot arrows to dowse flames. Again the aim should be for with some quests you could roleplay the heck out of stealth and let your stealth character shine. This wont stop other options to complete the quest (barbarian could kill the guards, or bribe, or intimate, or teleport..)