[random advice from the internet]
The concern I have is with the pricing and how it positions the product with the sort of customers that the business probably needs to be sustainable.
1. The value of the product is anchored to zero dollars.
2. The high end of the product is <$600/year. That means that landing 100 really good customers is not enough to make the business work. And that also means that it is not worth the effort to sell to good customers and therefore it is not worth developing a product that those customers might buy.
3. Sure there's a $15 plan. Getting to $10k a month for something that might work as a lifestyle business means retaining about 700 customers which even with a low churn means more than a thousand sales a day...all while competing against the company's own free plan..and GitHub...and a developer just making their own site.
4. The free plan might provide leads, but it does not provide qualified leads in the sense that qualified leads are qualified because they are able and likely to pay. One traditional way that company's try to move unqualified leads attracted by a free tier to their paid version is by adding 'features' to the free version that deliberately make it suck over time. The temptation is always there even though it doesn't work very well even for The New York Times.
My advice: be fearless with your pricing. The free tier is a way of avoiding the fact that most people (and possibly everyone) is going to say 'no'. The middle tier price is a 'recurring credit card charge that hopefully goes unnoticed'.
The high tier doesn't signal a viable business to customers for whom the product meets an important business need and therefore suggests it is probably not worth betting the time and effort to incorporate the product into its workflow. If eighteen months from now Releasepage is abandoned your customers' customers will be clicking on a dead link and that will reflect badly on your customers.
In the end, you want customers who are willing to spend money. Customers who are always looking to not spend money require tend to be more work and less patient due to their view of business as a short term zero sum game rather than long term set of mutually beneficial relationships.
Finally, I'd recommend Patio11's blog and Kalzumeus Podcast
Good luck.