You can use Adblock to remove the Archive button and the Archive tab on the left, but you can't move the Delete button back to where it was unless you also block the "Move" button as well.

http://www.emailquestions.com/threads/how-to-remov...

Be careful you don't block the whole bar. It will try to block two elements when you try to block the Archive button, but make sure you do only the archive button and not the other one (multi something, I think). You can use the same method to block the archive section on the left pane as well.

If you accidentally block the entire bar, click on Adblock, Options, Add Your Own Filters tab and remove the one that is not the archive button, then reload the page. I hate that we are forced to resort to this **** because of irresponsible and careless decisions from these businesses.