Page Assignments CAN, in fact, be used for the Home Page.
When creating a new Page Assignment, for “Object Type”, rather than putting “Account”, “Contact”, etc., you can select “Other Situation” from the drop down, and then enter arbitrary text, e.g. “HomePage”. Enter something arbitrary for Action Type, as long as it is consistent, e.g. “Tab”. Then you can have as many of these as you want, for every Profile if you desire, and an org-default.
Then, for your Home Page Visualforce override page, use this syntax for the Skuid Page component:
<skuid:page objectType=“HomePage” actionType=“Tab”/>
