Hey and welcome to the forums!
Your idea of 'converting' resources is very creative, but unfortunately it can easily be abused, and it's been ruled out by Supercell, probably for one of the following reasons:
1.Players would convert resources instead of buying gems.
2.Supercell would lose profits due to a fall in gem sales.
For a list of more ruled out ideas, and advice on how to post, please read the sticky by clicking
HERE.
Please be sure to read the stickies before creating or posting in threads on the forums, in order to avoid posting ruled- out ideas, or posting against the forum rules. Clash On!