I collect mostly Topps, Bowman and Fleer baseball sets, but as a kid I ended up with several 1960 Leaf cards. Sometime back I decided to complete that set, which has 144 basic cards. No real big name stars ( Topps contracts were exclusive with many players for packaging with gum, candy or confections) and so fairly inexpensive. But there are some challenges for a master set.
There are 8 prototype ( Big Head ) cards that are very pricey. One example is the Moryn below, the only one of the pre production cards I have. They have regular backs. The packs are also pricey, particularly the scarcer series 2. The packs have marbles instead of gum to try to avoid the Topps exclusivity clause mentioned above. In 63 Fleer would try a cookie
There is one recognized variation that is fairly easy. Card 25 can picture Jim Grant or Brooks Lawrence. Nether it very hard. But there are 3 versions of card 58, Hal Smith of the Cardinals, and 2 are tough, one really tough. Common is the version with his name and team on the back. Less common is one with his team missing. And very scarce is the version with his former team blacked out.
The Schroll and Groth are just unrecognized recurring print defects