Thanks for the input fellas. I agree that it'd be nice to see even just a small amount of semi-useful stuff pop as common items in the Mystery Box.
However our intention with these was to make it as it is; lots of stuff. Mostly random, cosmetic, bleh with chances to hit a ton of big items, cheap.
Hence why I did throw Crystal Keys, God Pages, Onyx, and some other items that pop semi-commonly to make up for that gap from common to rare.
I am soon going to be introducing Super Mystery Boxes, bit more costly, ton more useful items (may implement the skilling supply idea here?)
And much better chances to hit some other awesome stuff (to be determined exactly what that is).
Chiming off of what Enz said, yeah you can buy some good skilling supplies from the Supplies Donor Store but, I get where y'all (xVercii, DropsRS) are coming from. :P
Thank you