sneak attacks pretty weak
In the grand scheme of things, sneak attack dice are extremely, and I mean extremely weak.
Once in a while, yeah, your rogue pulls off some stupendous damage dice...but actually, I bet if you count the damage total, it's only a little more than that barbarian does every round. All day.
Why are sneak attack dice so lame?
1) You gotta hit to use them
2) Defender must be in a special condition (flanked, lost dex., etc.)
3) Class abilities can nullify it (barbarian, etc.)
4) Any concealment nullifies it (blur spell=immunity from sneak attacks)
5) Armor of fort nullifies it.
6) Vast numbers of monsters are immune to it (undead, constructs, monsters too tall to sneak attack)
7) the list goes on and on.
Basically, a rogue, played correctly, MIGHT be able to sneak attack 50% of the time. Maybe. That's the upper limit. Most of the time it's probably closer to 40% or 30%.
The long-term statistics are always brutal for rogues in combat. Dont' beleive me? Next time you are in a combat with a rogue, count the number of attacks that get sneak attack damage vs. the total number of attacks the rogue could have had if the rogue didn't have to worry about trying to GET sneak attack damage (meaning, if the rogue took full round attacks, dont' move as much, tumbling not required, etc.). Sneak attack dice in the long term reeketh. It's far better to just hit hard all day all the time.
Particularly at higher levels. Is there anything sadder than a rogue20? What, exactly, at that level is NOT going to be immune to and/all sneak attacks? A cloak of blur is just 25k for goodness sake! Throw in scary monsters, fort armor, and etc. and it's just stupid.