What are examples of balance a ticket?

Historically balanced tickets in the past few years:

Ronald Reagan, a very conservative candidate, chose the more moderate George H.W. Bush as his running mate in 1980.

John McCain, a moderate Republican, chose Sarah Palin who is a very conservative and rather young woman, as his running mate in the 2008 election. He also hoped this would add the appeal of the ticket to women.

When JFK, a New Englander, chose lyndon B Johnson from Texas, it was in an attempt to gain support from Southern Democrats.

These are just a few, because I think if you look at most presidential elections throughout history (since the 12th Amendment in 1804 which split the ballots for Vice President and President) you will find that most candidates chose someone as their running mate who will in some way complement their strengths and add greater appeal to the ticket as a whole.