Skip the sunset from your hotel window. Meet at Lan Xin, head out with whoever turns up, and catch the light over Shanghai together.
An open meetup, not a guided tour: no guide, just people who want to see the sunset with company. About 75 minutes at an easy pace. It starts 45 minutes before sunset so you're somewhere good when the light turns, then loops back to Lan Xin, so food and drinks are right there. Your photos from the walk show up on the page, and the next travellers decide to come because of them.
Bring Comfortable shoes, a light layer for after sunset, and your camera