With election cycles approaching two years. Whoever gets elected will spend half of their first term campaigning for Re-election. Elections need to have a designated start and end date, just like many other large countries around the world.
A single 4 year term is to short, and 8 would be to long for a bad president. Considering President Obama's own re-election, and campaigning for Clinton; He basically had 6 of 8 years to do his job. First term he lost a lot of valuable time, and many decisions are based on how voters will react.
Trying to shorten the election wont work, because opponents are going to keep trying to Campaign earlier and earlier, forcing whoever the president is to do the same. The President can do HIS/HER job better if we change the Presidency to a 6 years, 1 term.