It may just be me, but I'd find it useful to have a Search option that only returns checked-in assets. At the moment (unless I'm missing something) it always returns both checked-in assets and referenced-only assets and doesn't distinguish between them.
That is, if I search for all assets inside a folder tree and there's a sequence using a load of clips, those clips are always returned even if they aren't actually checked into that tree anywhere. To tell if an asset is actually checked in I then have to use GetChildren on its parent folder to see if it gets returned.
And I don't know if any enhancements are planned to the other Search parameters, but it would also be handy to define a User attribute as having a date value (at the moment date-based searches are restricted to System attributes).
And to go the whole hog it would be nice to have STARTS_WITH and ENDS_WITH conditions for strings, or maybe even simple wildcard-matching.