i also see a backup wallet feature, but no restore feature.
It's pretty much assumed that restoring is an unusual event, when you've lost your main system.
and the sign feature is pretty much useless as there is no validate feature, so whats the point of making signed messages that no one can easily verify.
bitcoind has a verification function. Sign Message is needed for everyone, but only people asking for the signatures need the ability to verify. Nevertheless, a Verify Message dialog is planned for 0.7.
I filed two issues for the intuitiveness problems mentioned:
Bitcoin-Qt: Label use non-intuitive to newbies: appears to be per-transaction rather than per-address and
Bitcoin-Qt Export function non-intuitive