1953 Baseball - Jim Suchecki has popped up as another unissued artwork
1956 Baseball Buttons - The buttons (or pins, if you will), were issued in a small box, not an envelope:
1949 Flip-o-Vision - Nos. 8 (Jimmy Wakely in "Dating Time", 49 (Cab Calloway in "Hi-De-Ho"& 52 (The Aldrich Family in "Balloon Goons") were identified in Card Collectors Bulletin #68 as having two subjects possible for each number. This is not verified but I am hoping someone can provide scans of alternate subjects if they exist.
1955 Davy Crockett Tatoo - Dating on a retail box makes this a 1955 issue, not 1956
There are also a few formatting issues in the printed on demand version I hope to correct at some point but I currently don't have the proper software to do so. If an update happens, I'll certainly post details here and on the main hobby online forums.