I'm also going on my first trip to Tokyo, any recommendations??

I'm flying into Tokyo Gimpo/Incheon at 7:45 AM and returning at 8:00 PM
It's a full-time 3-day, 2-night trip from Friday to Sunday, and I've booked accommodation in the Shinjuku area, but I haven't decided where to go yet
One thing I've thought of is going to a trendy Samurai Bar to see a fire show
Are there any other places you would recommend??