The only thing I miss in WordPress is the possibility to backup and restore without plugins. I mean, a proper backup and restore tool. The backup can include Files and Database. Then you don't have to restore or backup the hole WordPress.
Maybe it can be a service offered from wordpres.org like AKISMET and STATS.
I think people will pay for a proper backup tool, and also having an online backup. I pay to my hosting provider for a backup that it's not special for WordPress.
For example, could be like TimeMachine from Apple (witch I think is the best way to do a Backup since I know). In TimeMachine you have several copies at different times, and search for the differences.
I think that will make WordPress even better.
Just a suggestion