President Obama should do as much as he wants and is in his power before he leaves office. Republicans did as much in the opposite spirit by not helping get a Supreme Court Justice in before his term was up. But "politics" aside, if acts are within his right, one can not disregard them. And you don't get to be president again, so it would be best to make the most of it.
Yes, Obama should make as many agreements and policies as possible before he leaves office. The more agreements and policies he makes, the less it is likely that Trump can reverse all of them. This especially holds true for agreements and policies that benefit a lot of people. Trump will be hesitant to reverse these measures.
A President only pardons people and comes up with eleventh hour new agreements at the end of a Presidency when they know that what they are about to do is unpopular. If they don't want to be held accountable for something, they will wait until the last minute. That is not what the Presidency is about.
Obama should increase trade relations with Cuba and other nations.This will help the U.S.'s economy.However he shouldn't accept every single policy.He should make agreements and policies that benefit the U.S. He could harm the nation by accepting too many agreements. This can happen by increasing trade agreements that will harm domestic industries.