I can totally understand the concern.
The reason we position ourself in this particular sector of the market is that simple adventures are very easy to come by; in addition this particular thing is something we - with admitted bias - believe we are very good at. We've always said that we write for experienced GMs and DMs, and that there are hundreds of adventures out there for those looking for something a little simpler.
I personally believe that a more complex story, more interesting NPCs, and so on is extremely rewarding. We've received feedback time and time again that the level of immersion in WotBS was outstanding, and it's a style we're eager to explore further.
I hope we've made some innovations thorughout this adventure path which complement the style - for example, the player handout of NPCs that Ryan mentioned above. There's a new one for each adventure, with each NPC updated, because we, too, agree that when the players can't remember who an NPC is that's a problem. So the handout will say things like
"This is Bobby the Halfling Spy. You met him in the Four-Dragon tavern while hiding from Orcus' secret police, and he told you about the mysterious network of tunnels beneath the city. He was very insistent on locating the Golden Chalice of Everdrinking, and is notable for having three legs." (I just made that example up, of course - there's no Bobby, Four-Dragon tavern, Orcus, chalice, or mysterious network of tunnels, and that's a spectacularly poor piece of text). Plus we have the free guides (and make a point of explaining the entire campaign to the GM/DM before you start).
WotC, for example, tends to pitch its material towards the more casual or beginner gamer (which is fine - it's just not our cup of tea). We're aiming for those looking for something a bit more complex and immersive. That's not everyone, admittedly - and there's nothing wrong with wanting a more straightforward episodic style campaign, but I feel there's so much of that already out there that we wouldn't really be adding anything.
We do hope you'll give it a try at least; I think you may be pleasantly surprised. It's free, so I'd say it's worth a little try.
