Here's an old post regarding porch ceilings. We have stained T & G pine and love it. As for stain color, we had it custom mixed. However just go to your local paint store and see how the stains look on pine. The type of wood will really impact how the stain appears. Here is a link that might be useful: Porch Ceiling Link

Don't use Tung Oil! It's not durable for exterior. If there was any way for you to get a coat of Cetol 1 on the backside of the ceiling, it would help a LOT. The idea being...your wood would be much more sealed-off from water movement into the BACKside of the ceiling. >>> Same idea for wood siding shakes...If they're back-stained or primed, they last much longer. Even the best mildicides are effective only for a year or two in that environment.... You're in FPE country!! Their Marine Varnish is superb...spendy, but superb. Very good info. on this FPE link... Faron Here is a link that might be useful: FPE Varnishes...

The same as your trim, in flat finish...

MinkaAir makes very nice switch units that combine variable speed for the fan as well as control for the lights. I must have half a dozen of these in various places in my house. Amusingly, they are battery operated and RF. I realized this when I was holding one in my hand not installed and realized it was controlling the fan.