Don't know about your needs but not much of our stuff would even fit in there other than tractors. For me minimum 2 feet higher and for the bays across the front use a beam and make them 32 feet.

In 16 feet openings you can drive in one truck. In 32 foot openings you can get three. Wider openings will give you more total usable shed space.

Putting a beam across the front you will need more height because the beam will take up some of the overhead.

John