I have been to Africa, Canada, and Australia, and always bought the non refundable tickets. I do buy the travel insurance though, because you never know. While I may be out a deposit, I will at least get my airfare taken care of if I get sick or something and can't go.
I also use and SKB double bow case for traveling and it works great. I can fit 2 bows, arrows, and al ot of my gear, and some of my clothes (for padding) in my case. I have yet to go on a trip where I could get everything into one bag though. Last time i checked, the overwieght fee was more than $25, but if that is all it is, and I could get everything in the one case, I would do it!
I also carry my electronic stuff, like camera, rangefinder and such in my carry on bag.
Bisch