If you are thinking about what to collect, I have created an app, Collection Suggestion, to help you get started. You will select an option from 4 categories (difficulty level, total number of coins, condition, and composition). After selecting from each category, you will see up to 5 suggestions with a brief description of each.
Right now, it is mostly consisting of 20th century coins. There are a few suggestions of 19th century coins and I hope to add more in the future.
On the left side of the screen, or top on mobile device. Select one of the 3 options and click the Next Category button.
After clicking the Next Category button, the selection will be added to the right side, or below on mobile. You can click the Change button next to it at any time to change your selection.
Once you select the last category and click Next Category, the button changes to Get Suggestions.
When you click the Get Suggestions button, you’ll get a pop-up with up to 5 suggestions of what to collect. You can click on each one for a brief description. You can go back and make changes by clicking the X on the top right of the pop-up.