Thank you for your comment, @Amalthee_Vetements_e!
I’m afraid we had to limit the number of displayed pins to ensure the widget works properly and looks good. At the moment, we don’t have any specific updates regarding this request, but our devs may consider it for future releases. We’ll be happy to update you here if there is any news.
Also, I’ve created another feature request on your behalf: Show more than three images in a board. Let’s see what other users think about it, too 
Thanks a lot for your help!