Dad car, but fun to drive

Have you considered a VW Sportwagen? I own a 2012 TDI model that would check most of the boxes you listed, if you can wait long enough for the diesel "fix" to be sorted out. If you can't wait, the earlier 2.5 L engine and more recent 1.8 L turbo will also provide similar smiles with good fuel economy. If your sense of speed is calibrated to the race track, look elsewhere.

The wagon format gets no street cred, but is my favorite feature of this car. Storage like an SUV when you need it (22 bags of mulch!). Car practicality all day long.

If you consider this route, I STRONGLY recommend a standard manual transmission rather than the DSG auto. The DSG (in my car, anyway) is wholly unpredictable, even in " manual" mode, and destroys a crucial connection to the car.

What about Cadillac CTS wagon? It meets most of your needs and a 2010 / 2011 should be in your price range.

The Mazda6 is roomier than a Civic, very fuel efficient for its size, reliable, and relatively fun to drive.

If you're referring to the current Fusion, they're reliable in our stats from the 2014 on.

An Infiniti G37 is more powerful than the Mazda or Ford, but no more fuel efficient than your Maxima.

The Acura TSX wagon is probably also worth a look, if you can find one within your budget.

If the Buick Verano 2.0T is too small, the Buick Regal 2.0T might as both should be around $15,000.