I use Wordpress for over 10 years and my biggest problem are the CMS Detectors, I don’t want anybody to know wich cms is running on my Site, I think WP needs this features in core.
Security Settings (on intallation random name for admin folder will be generated) everything that shows detectors that this is wp need to be changed.
Buy the teams behing succeful Plugins like WPML and make it part of something called WP Pro so this WP will have features like Multilingual.
Inside the Editor a setting to choose the Menu where this page will go.
Every page need to be able to have its own Theme.
What you think and what are the feature you would like to have in WordPress?