Shortcut for dragging and dropping a tab on terminal
There is no such shortcut in Terminal (apart of dragging the tabs manually), however such feature works fine out-of-box in Term2 by hitting Shift-CMD-←/→.

Another way is to have tabs in separate windows (CMD-N)and switch between them by CMD-1,2,3, etc in order you like.

See also: Keyboard shortcut to jump between tabs on OS X Terminal