The next 10-15 years are going to be tumultuous, regardless of who our next presidents turn out to be. The most disruptive issues are extremely complicated and will amount to delicate balancing acts. Obama grasps them, at least. This is a great interview.
Looking back: my biggest gripes about Obama are 1.) how he perpetuated our drone war, failing to create clear rules around who gets killed and why, 2.) failed in administration transparency for his first 3-4 years, 3.) perpetuated unlawful domestic surveillance programs, and covered for a misguided intelligence community, 4.) gave blanket amnesty to Bush-era officials for their torture programs, 5.) invoked presidential executive orders that unnecessarily expanded the power of his office (not so great when tyrants come to power, ahem, Trump!) and blunted constitutional checks on power by setting new precedents (ex. #1, a US citizen was assassinated w/o any due process, mic drop), 6.) Libya, 7.) basically no response to Russian incursions in Eastern Europe that is taken seriously by Russians, 8.) failed to properly steer Clinton when she was secretary of state or reprimand her for a.) personal email system, b.) Clinton Foundation ties with Russian uranium mining interests and Haitian relief foreign aid (both reported on by the NYT and others).
That said, he was a good president, and Obamacare isn’t the cardinal sin that Republicans make it out to be. I don’t agree with most of his ideological standpoints, but I think he’s a decent person.