This is approximately what I do as well, and would highly recommend. The one caveat I would add is while you are researching things you might want to do, take note of the subset of things you most want to do, and make sure you know what days/times they are open, if you need to book in advance, etc. I am very against having a hard schedule, but I also don't want to travel somewhere only to miss the one thing I was really looking forward to because I decided "I'll do that tomorrow," only to find out it was closed the next day.

An additional pro-tip: Make your first list of things you might want to do ahead of time, and name it after the place you are going, e.g. "New York." Then while you're traveling, make a second list of "favorites", e.g. "New York Favorites." Keep track of all the restaurants, activities, view points, etc that you enjoyed using that second list. Then whenever someone asks for recommendations for a particular location, you can just send them your favorites list.