My first submission for your project, If there any request such color option or anything, i really open for any of those, and I love to do any request if there are any.
I like #22 and #23 better than the others. I like the "formality" of them. The do feel familiar, however, like I've seen them before. Also, the font is not quite right. #24 looks too much like a 3 and #21 looks too much like a stop sign. A stop sign is the last thing I want a customer thinking about before buying, right? Very cool, keep it up.
Thanks for your feedback, really appreciated. Here's new font type for optional, hope you will love it. If there any request for anything, please let me know it, thanks.