Don't know what ammunition you are using, or what barrel length, but 3" high at 100might be a bit more elevation than you need for 200.
I'm sure that there will be folks there who can give you the come-ups for the different ranges. Should be able to get on with the allocated sighters.
Are you going to use the elevation calibrations on the sight, or go with the gate up, and count clicks? If you have a 100 zero, you should be able to apply the necessary elevation corrections.
Do you have wind charts for your ammunition, and a washer on a string tied to your left wrist?
Keep dry in the rain? Well, a rain suit is a start. A light poncho/tarp is useful to put over your gear. Ziplock bags are really useful for keeping scorecards dry. But don't worry about getting wet, or waste time trying to stay dry.
Hungry - I'll be at Connaught Fri-Sat-Sunday for the MilCun wind reading course. See you there.