Watching Part II on AMC tonight, I was reminded of why when I was younger I originally thought it was better than Part I, and make no mistake Part I is a classic, but Part II is a lot more complex. Due to complexity, there are going to be more questionable plot holes, but the attention to detail, intricate weaving of the timelines and stories together had me once again questioning if Part II was actually better.
The amount of care and thought put into the complexity of the whole situation by Zemeckis is really admirable, and I still think it might be better as a result. Truly an amazing sequel.