I had an IDEA

Last night before I went to sleep after playing clash I had a great idea. The game should offer an exchange building (outpost). The cost of this building could be in gems or dark elixir since both are the most valuable. Coins are used for building the defenses while elixir is used for troops and the rest. Dark elixir is only used for higher end troops. As I was typing this, I thought of the upgrades for this "outpost". Each upgrade could enable the exchange rate to go up a little more (similar to the rage spell but not so drastically). Since coins are the most needed these should have a higher exchange rate. I do not have an idea for how to properly measure the different types but my thought was something like: 10:1 - elixir to coin (every 10 elixir is worth 1 coin). I have no idea for the rest. The dark elixir isn't produced as fast as the coins and elixir, so the dark elixir should get more coins than the elixir (depending on ratios). You could even work gems into there with something outrageous like 1,000,000:1 (preferably something better).
I came up with this idea because my town hall is currently level 7 and I only need coins to upgrade at this point (excluding researchable troops). I leave this idea up to you to follow through with or shut down. You would be in charge of coming up with a better name to make it more "clashy".

Thank you,
Bleibs (town hall level 7 please visit and no attacks; just click next village, i need my money :P)