I will make the requirements for leather lower soon, probably around Christmas!
You can also buy hides from a Hunter in Amber Wilds.
One of the reasons the Combat Exp takes longer to accumulate is because there are less Skills that use it compared to Craft Exp. I may re-balance it in the future though as this system is pretty early in development still.
Lastly, don't feel obliged to send me anything, this is mostly a passion project for me that I enjoy working on :)