Still the lack of documentation is kinda sad. It just means countless hours wasted "relearning" the same thing by each developer.
I guess the best entity to address your concerns would be Oracle, since they own the development of this db.
But I believe there might be a doc with the format of these files, somewhere.
Inside the DB itself, there are satoshi specific "key-value" records, which indeed would be nice to have somewhere on the wiki, but AFAIK there is no such page.
And moreover it's getting changed as we speak - a new type of "keymeta" records are coming...
Up to v.0.8.3, the possible
key-types were: name, tx, acentry, key, wkey, mkey, ckey, defaultkey, pool, version, cscript, orderposnext
Most of the key-types are followed with additional data (i.e. tx is followed by its hash). The key-type plus this additional data is the actual DB key.
As for the format of the
value, you'd need to analyze the source code. Check ReadKeyValue in walletdb.cpp