actually, the simplest solution is to not clutter the thread with requests. people watch this thread, so yes, anything that creates a notification for a post not containing a card is clutter.
a separate thread for requests where posters linked to where they'd filled them wouldn't be unwieldy at all, but people won't do that if they can just take advantage of the high traffic here, so clutter it is.
put your reference photos under spoilers and we'll live.
edit: the post i was replying to has since been deleted, and i forgot to quote