We all would like a button to do all this stuff but that would, and does, make for highly complex themes. And the themes that have buttons for uploading images to one place don't have buttons for others.
That's why I like Atahualpa. It gives you a bunch more flexibility but you do need to know how to use an FTP client and understand CSS to some extent. But using and FTP client is standard for website development. Like if you had a problem with a plugin and couldn't login to your site how would you delete the plugin without using FTP?
With that said how did you get the original header images uploaded? Also to have "a button" you could use a plugin for the headers that has that function but then you are going to have to learn how to add the code to the proper place in the theme options or perhaps learn how to add a new widget area to put the header widget.
(CNY Web Designs
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