Hello eric! Took a break from my site work to pop in and look around.
Saw your suggestion, also saw your required amount of mars dollars to obtain the payout.
Try this, create another landing page that members will randomly land on when they click on the ruins page link. Make it something like Square Deal Sams Grab bags. Have like 4 grab bags to purchase. Figure out a proitable percentage for the site using a percentage scale. Have everything in those grab bags, including upgrades, 48 hour attack proof defense, a one time never lose attack, a base finder good for 4 hours, a 20% increate of MM found for 12 hours. Use you imagination.

Ask your members for ideas.
But have at least 2 of those grab bags filled always with dust. One grab bag with almost the same amount of money that the member paid for. One with a slight increase and/or every so often a Great game item or multiple game items.
You need to have it set so the same order of the bags don't pay the same always.
Sell those bags at moderate to very high prices. Make the prices radom, as well as the contents. This should help you reduce the mars dollars in the game and make members happy to get speciality, rare, or great items.
Good luck with your site!