I would like to see Samba 2.2 support, with better management facilities and a built-in ability to emulate Windows 2000 servers (available in Samba 2.2), to provide needed services such as Active Directory and IntelliMirror.
I would also like to be able to change domain (ie. e-smith) passwords -- especially in 9x/ME -- from the Windows User control panel, without having to go to /e-smith-password/.