BX-FR Alignment Dilemma

I think I have finally decided what to do for the alignment system in my new game. Initially I had been leaning toward using the AD&D alignment system since all my books have the dieties and NPC's and magic item alignments in terms of the 9 pt alignment system from 1st ed AD&D.

However, I have never been a fan of the interaction of know alignment, and detect evil type spells and abilities with alignment systems that contain "good" and "evil". I really like the concept of Lawful, Neutral, Chaotic as three buckets for grouping the world generally into "teams". You have the forces of order (generally thought of as the good guys) the neutral rogues who are mostly unaligned and are looking out for themselves, and finally the forces of chaos. However, even a character with a chaotic alignment isn't necessarily "evil".

I read a really good post from Robertson games blog here which describes their use of the three point alignment system. I don't really agree 100% with the concept of making chaotic characters be evil and then turned over to the DM as NPC's - instead I'm planning on playing it more like the Moldvay core rule (essentially with a lot of room for interpretation). However, I think I will be borrowing the Robertson games post's idea of having a Lawful tongue, a neutral alignment language, and finally - the Black Tongue which I really like both in name and in spirit.

I've also been tossing around the idea of a "taint" system but not played out the same way as the Unearthed Arcana version. If I can pull something together around that I think it could be a good roleplay aid.