Dear friend,

Thanks for contacting Top China Travel!
 

As for visa requirements, as far as I know, there is no AGE LIMITS to senior travelers. And it is recommended that you re-confirm with the Chinese Embassy in USA. You can look through  the website of Chinese Embasy in USA for your reference, and you can contact them for consulting and getting useful information.

However, we suggest that your families can accompany with you for your China travel because you may need the assistance of your families during your trip in China, including waiting at the attractions and get on and off the trains.

And it is not recommended that you join the group tours because the difference of ages of the travelers in a group may be large, and the guide may not take good care of your during this period. It is recommended that you customize your tour with the travel agencies. On the one hand, you can decide your itinerary. On the other hand, you can be assisted by your families.
 

Hope my advice is helpful to you.