So, some random thoughts as I read through this:
Robes shouldn't cover all of your eq. Symbols, hands (both gloves and weapons), feet, wrists, fingers, neck, and head should all be exposed. This basically means if someone wants their robe to actually make them hard to identify, they lose 6+ eq slots worth of enchants and mods, making them combat-worthless, but still have a purpose RP-wise and aren't cheap for PK and whatnot. Don't make robes do ANYTHING more - no junking of eq on death or any other feature that makes them impossible to identify. Robes shouldn't hide your description or adjective, either.
Hoods present a more complex problem. They shouldn't alter/hide your adjective, as that makes diguise usless, and it presents all the other issues people keep talking about. It's not realistic to have them hide your description, because any decent description talks about more than just the face. It COULD however, hide your gender or your race, when used in tandem with robes. Thus, a robed/hooded person would appear like this:
Code:
A descriptive half-elf is here.
OR
Code:
A descriptive male is here.
We still face the problem of the description - if you look at the half-elf, his description will almost certainly say "man" or "half-elf" somewhere, belying the robe/hood.
Overall, this just seems like a huge hassle, but it sounds cool
if it can be worked out. This isn't a feature that should be used as a crutch to maintain secrecy, but just another tool to play with in this big old sandbox of RP and PK.