I think your price is bordering on the high side but that's not the main issue. . It's hard to say what the real issue is, or maybe there are several issues.
Usually, I am a sucker for a pretty blank but, to be frank, the blanks you show do not turn me on. . Based on colors, the first view of blank #8 comes closest, but the second view does not help. .The colors of the others do not appeal. . The blanks with the mini-cones have an uninteresting arrangement of cones and the color of the resin is not inspiring. . For the other blanks, the large wood piece has a boring shape and I do not find the color (or color mix) in the resin portion to be an appropriate match or contrast to the wood.
I would recommend you try for a more "natural" appeal ... random arrangement of cones, "natural edges" and shapes for the wood fragments, perhaps a bit of glitter and also some swirl patterns in your resin. . Take care that any color mixes are artistic. . Emphasize the grain of woods.
For blank #5, the white needles do not add anything.
I fear that I may be coming across as "brutally critical", and I am sorry if I do. . I am sure that if I had made those blanks I would be quite pleased.
I speak as one who has never done any of my own casting. . And I do appreciate the challenges of blank casting as a general artistic endeavor.
I also speak as one who has made over two thousand pens, using blanks from nearly every vendor that I have encountered.
There are lots of examples of appealing custom-cast blanks at the various vendors, as well as here on IAP. . Check them out. .
Also, try making some pens from your blanks and learn from how those results turn out. . I think that the "art" of blank making is strongly coupled to the visual appeal of a finished pen and you have to make your blanks with that in mind. . In my view there is more to it than just placing some bits into the mold and adding some resin. . You need to think of the end results, and you can do that only if you have some experience to go on.
I don't recall seeing any previous blank offerings from you, although I could have missed them. . Also, I don't recall seeing many finished pens made by you. . Some of the latter would be quite a help in selling blanks, I would think. . There are a large variety of pen styles, ranging from the elementary slimline to the full-size Emperor and Statesman. . Different pen styles often dictate to the pen maker what is an appropriate blank to go with them, especially when you are considering a custom-cast blank.
So I would encourage you to make a few pens with your own blanks and also to look around at what else is available from custom casters at some of the major pen-supply vendors. . Keep trying. . Don't be discouraged. . Keep your eyes open for what pen makers are using on their pens.
It's not an easy job for pen makers to sell the pens that they make. . Perhaps you can make that job easier by providing some really eye-catching blanks. . And sometimes it is the most simple ... and novel ... ideas and designs that sell the best. . I know it is not easy to be an artist, and making pen blanks is very much an artistic pursuit.