Since you've already done the Olympic Peninsula, I would recommend following Adventuring Cycling Association's new Washington Parks route in a clockwise direction from Anacortes to Winthrop to Wenatchee to Yakima to Mt Rainier National Park. After Mt. Rainier, you could hook up with the ACA Pacific Coast route at Centralia.

You'll have to do the math yourself, but I think this route would be just about right for your 14 day timeframe.