As far as I know soft cap means minimum amount of funds raised for project to start. If soft cap is not reached, investors (can) receive their money back. But you say that the project will continue anyway, even if soft cap is not reached. What is the purpose of soft cap then?
Anyway, idea is interesting, in my opinion the important part of Rowan Coin is free distribution to environmentally conscious people as reward, and not so much the fundraising part, so I don't understand why you need minimum $500,000.