We have done both and both have positives and negatives. Honestly the 1:00+ time is more relaxing. By the time you get in there, your room is open (about 1:30), no lines in the terminal, no one ahead of you to take a sail away picture, no huge crowds blocking the entrance, no piles of luggage to navigate around. But the downside is you might miss lunch. You might miss a particular set of meet and greet tickets you want. That being said, there is food on deck after lunch, a wide variety in my opinion. And I am personally a bit over the ticketed events. Characters are available throughout the cruise without tickets as well.
Whenever we arrive early, I feel a bit smug like I've done what I could to get every second/dollar out of my vacation. It feels like i am doing what i am supposed to do because it is the most logical. We get lunch, stand in line for tickets, walk around, etc. Our kids have actually never gone to swim at this boarding time-- not sure why but they have wanted to do other things. So both have pluses and minuses.