Great idea, but I'm going into San Jose and out of Liberia.
It turns out that my flight with Nature Air was cancelled and I'm now doing Arenal to Manuel Antonio by van. At least that will eliminate some of my baggage issues, and by the time I take Sansa, we'll have used up some of the stuff we are taking (sunscreen, Repel) and if I bring some "disposible" clothes for the hiking (old T shirts that I don't love, etc), I'll be able to make everything work.
But thanks to this forum, I won't even try bringing more than 30 lbs. checked and 10 carryon.