Well, in your previous post you said you would always take the side of any resistance movement against any Empire... now you have narrowed the kind of resistance movement quite a bit.
And there are works of fiction in which "the Empire" is benevolent... Think of the emperor in the Mulan movie. Aragorn' kingdom of Gondor and Arnor could be considered an Empire too. The Fel Empire from the Star Wars Expanded Universe, the Malazan Empire from the Malazan Book of the Fallen, the Empire of the Star from the Eldraeverse and the Tamul Empire from The Tamuli by David Eddingswas are quite nice too...
For real life examples, look for information about the Five Good Emperors of the Roman Empire...