No, $30 is the donation required to get the game. $50 is the amount required for beta testing and early access (access to the current 1.05 onwards before the release).
As for inconsistencies of the art work, I was referring to the significant difference in stroke thickness and level of detail between the battle sprites and the event CGs. Notice that the CGs are a lot more "bland" as compared to the sprites. And yes, I was also referring to some of the placeholder images which are weirdly out of place. I assume they have been replaced as per your comment.
Though, $30 might not be the actual price of the final product, as crowd-funded projects usually demand more during the development period (one reason is to reduce risks, the other is the assumption that part of the amount is goodwill coming from backers, the price to "make it happen" rather than an exchange for a copy of the product). Products tend to become more "economical" once development is completed.