For your intended purposes I would go with a Titanium hard tail 29er and buy both a front suspension fork and a rigid fork and switch them out depending on the type of trail/road you will be riding on each excursion.
The big wheel will be perfect for your type of riding. You can get that big wheel rolling and make some time, it will make it more like a road bike in that regard.
The titanium will absorb the bumps and vibrations and reduce the wear and tear on your hands, back, and shoulders.
You could go with either a cyclocross or a mountain bike geometry.
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