"Yikes. We couldn't find enough data about this website.
Most likely, there is not enough traffic to get a reliable result."
-Website statistic searches provided this quote.
I think that you should take a step back and look at your marketing plan. In order to sell any slots (ads or memberships) you must first have a reliable amount of traffic. Without traffic, there is no value to anyone purchasing any such slots for any amount of money.
I have never run a toplist site, but I assume the way you attract attention is by first doing self promotion by offering servers free trials or something similar until you have gathered enough attention.
SEO is a big deal with sites like this.
When I google "RSPS Toplist" Your site does not appear on any of the first 10 pages of results from google. I think that this should be a major focal point for you to work on fixing.
You seem to have a semi-large team working on this project, with a lot of talent and experience included.
I think that at this time, you shouldn't be focused earning any money, rather growing your audience.
I wish you the best of luck, but I personally would not invest a penny into the site at this point. (not saying I wouldn't sometime in the future)