Windows 8 includes both the Metro side of the coin as well as the standard Desktop. Your traditional apps will execute normally on the legacy Desktop. No change to the User. Metro applications are Touch oriented so of course they have different controls. They are SVG based so they will run on screens that are 7" to 70". Not sure why you feel they are "obviously written under the assumption your screen is 13" or smaller."
Your comments about IE seem to indicate you don't understand how to use Peek. Meaning, you can touch the left side of the screen and Peek at apps in Memory. IE 10 on the Desktop will support Plugins, like Flash. IE for Metro will not support Plugins. Which leads me to the next point. Apps don't "exit", they are suspended. Have you not looked at the Task Manager to learn this? And really, Plugins like Flash are nagware anymore anyway.HTML5 is native in Windows 8.
And to respond to your incorrect opening statement, Windows 8 is a Touch first OS that is always operable with a Mouse and Keyboard. Assuming the User is capable of operating them.
Why would you wants apps that "can't be Windowed" while running in Metro? You want to switch between them? Why not use Peek or SnapView or Charms like Search or Share? I am going to go out on a limb here and guess that you haven't really experienced Windows 8 Developer Preview on a Touch Device.
Another observation, Adobe CS4 adding 25 tiles to the Metro Desktop isn't an indictment of Windows 8 rather an editorial on the bloatware of said software suite.