It would be nice if more half grades were available other than just 9.5 when listing card details. If I'm adding a new SGC 7.5 slab I have to put it down as a 7. As a person who is a stickler for details who owns vintage in PSA and SGC slabs (a lot of half grades when grading vintage cards), this would be wonderful.
I wish I could learn more about how the backend is designed. My theory has no information, so I am very likely to be wrong. I'm guessing it's because the core backend database doesn't store all the possible grades. Which is why when you download the checklist .csv, it only gives "loose-price", and not graded cards. I think the sales history is pulling from ebay (or some other external source) and the checklist download is on internal servers.
All data is stored internally. prices, sales data, images, etc. Nothing is stored externally. The CSV download supports graded card prices if you are subscribed to the Legendary tier.
The technical difficulty in tracking half grades is backend and front end. The database changes to store those, the front end changes to display them, and the logic changes to process those grades, and then code changes to handle all of those across the site.
None of those are insurmountable, but adding features is always a trade off with other priorities. And there is data overload concerns too. The more data shown, sometimes makes it harder to see the important data that people care most about.
I wish I could learn more about how the backend is designed. My theory has no information, so I am very likely to be wrong. I'm guessing it's because the core backend database doesn't store all the possible grades. Which is why when you download the checklist .csv, it only gives "loose-price", and not graded cards. I think the sales history is pulling from ebay (or some other external source) and the checklist download is on internal servers.
I love the site and really appreciate the efforts that have gone into its development. I do think that the 8.5 half-grade, at a minimum, would be a huge addition to the grade offerings. I'm seeing more and more of them at my local card shows so it seems there is likely enough transactional history to support their addition.