So far I've noticed that the reagents I've found have a higher sell rate then crafting your own potions. You can get 2 gold for one Dragonthorn and 2 gold for one Blessed Thistle, yet when you combine them to make a potion, your potion's selling rate is 1 gold. I could have gotten 4 gold just selling the reagents. Maybe I'm not far enough level to notice any significant change in value, but right now all I really want to do with my reagents is sell them.