One of the major missing feature is the ability to set a title tag for a joomla article. You can set it by using a menu item but this can bit a nightmare to manage.

For an article, what should happen is you set all SEO data including the page title tag, robots info and all other required data for SEO meta kyewords (using mainly internally now), meta description and ability to add custom meta information. If the information is not filled in the default info can be used like now (globally setting here would be useful ie use article title or article meta description)

when using a menu item to display an article it is the SEO data from the article that should be used and any data that is filled in the menu item metadata should be ignored and possibly greyed out, or perhaps links to the data in the article so it can be edited in both places.

There are a lot of meta tools out there but they all seem to use there own database (ie sh404sef) to manipulate meta data and page titles rather that these systems using Joomla's core article database which make it easier to use other plugins and smoother upgrading.

Please vote for all the missing SEO feature especially the page title tag option (if the joomla team do that they will probably add the rest)