I think it's a great adventure. I
love site-based adventures, and B2 is a fine example of that genre. As already mentioned, it is generic enough to fit into any setting. In addition, it has a lot of great 'plot hooks' for future adventures (including further investigations into the 'Cult of Chaotic Evil' and that mysterious dungeon tunnel).
As for complaints about the 'monster condo' problem with the CoC, two easy solutions are available:
(a.) assume that the evil 'high priest' exerts a general authority over all the different humanoid tribes, thus preventing all-out war from breaking out; or
(b.) place the different cave complexes in different areas (iirc, even though many of the caves are interconnected, there are at least 3 distinct 'cave complexes' that can be separated out).
I actually used both solutions the last time I ran the module.
JohnSnow said:
... We had some great fun reusing the Keep in a Castles and Crusades game I played last year....
I'm glad you enjoyed it --
despite the fact that the evil priest in the Keep managed to deceive and betray your party at a crucial moment!
(Of course, making the priest an attractive female helped in the deception ...

)
JohnSnow said:
...
Of course, my favorite D&D adventure is still The Isle of Dread (X1).
That's a good one, but the greatest Basic/Expert D&D module of all time is B10 ('Night's Dark Terror'). I would urge anyone interested in seeing the Platonic Form of D&D modules with their own eyes to obtain a copy.
(I'm also a huge fan of the X4 & X5 series.)