Interesting idea. But I question the overall security philosophy of a project that includes so many suspected to be weak, known to be weak, or provably weak algorithms, e.g., MD2, MD4, MD5, SHA-1, and DES.

If this is for serious security, DROP THOSE NOW. Sorry to scream, but the sooner we stop using them, the better.

I also wouldn't spend a lot of time on AES 256, given some of the recently described weaknesses that reduce it to by many bits of strength. Better to work on CAST5, e.g.

Better yet, work on the RNG. Make sure the RNG is cryptographically secure. Without a cryptographically secure RNG, all the key derivation algorithms are pretty much useless.