All of your suggestions will be a significant downgrade in sound quality. For fun, try using another 2 channels of your multi 5 to biamp your speakers. Then you won't feel like you are wasting anything, and you will likely get a nice little improvement in sound quality.
If you are set on an integrated, be prepared to spend at least double what you were considering to match what you've got.
If you are set on an integrated, be prepared to spend at least double what you were considering to match what you've got.