If you use Categories in Outlook to identify and classify priorities or the type of work you have to do, you can work in a much less cluttered view of your Inbox. After categorizing your new items, click on the column heading called Categories. Click it again to put the uncategorized mail on the bottom.
To simplify your view, on the View tab, in the Arrangement group, click Expand/Collapse and choose Collapse All Groups. Now you are looking at a list of your work by priority or work type. Expand each one as you start to work on it. Then collapse it when you are shifting your focus to another.
You can also add a Search Folder for all categorized or a particular category of items, then add them to your Favorites on top. Right click your Search Folder listing in the Navigation Pane and choose New Search Folder. To create a general categorized mail search folder, just look for Categorized mail under Organizing Mail. Click the Choose button to select one or more categories for this search folder. If you use Favorites, keep it dynamic. Remove and add folders to Favorites as your projects and priorities change.