Ric,
Really depends on your aesthetic preference at that point. All metal roof systems can be adapted for use with solar panels.
Probably the easiest of those is standing seam, but all can be used with solar and perform fantastically.
On the energy efficiency front, need to know the roof construction details on the conditioned buildings.
Am considering a metal roof on my farm house and additionally on 3 barns. Also want to add solar panels on top of all 4 roof structures.
What are your recommendations on this combination of roof and energy application?