I am going to assume you are talking about hazel nut, not witch hazel - hazel nut is the one I have worked with. I usually just dry them and straighten them over a stove burner (use a hot pad!). They smell pretty nice when heated, and seem to stay straight pretty well. I would agree that spine is more important than weight...although once you get too much of a weight difference, long range shooting will be funky. 40-50 grains is not too much of a difference at closer ranges, although less is better. One thing you can do to reduce weight without affecting spine very much is to taper the last third (fletching end). You can reduce spine without reducing weight very much by sanding right in the middle of the shaft. If you make the arrow shorter, it reduces weight, but increases spine. You can't make the arrow longer (unless you do footed shafts), but you can use a heavier point to increase weight and reduce spine. There are a couple of older PA posts on this sort of thing with many more details. Good luck!