Quite welcome, @oneminja! I only spent that day in Hanoi, which included the bus ride from Ha Long Bay to Hanoi and back. That's the way cruises work, you can only get a taste of the place.
What I love about travel is getting immersed in the strangeness, as you call it. It can be frightening at first, but once your mind comes to accept that it can expand your horizons, travel can actually be liberating. Anyway, I remember the craziness of the rush hour traffic (the cruise also stopped in Ho Chih Minh City, which may actually have a worse rush hour than Hanoi). Whole families balanced with all their possessions on one moped, trying to navigate through all l the chaos. But there's also the opportunity for incredibly peaceful moments in unexpected places, such as a park, temple, or lakeside picnic.
As an aside, I visited the "Hanoi Hilton" and thought that, as a US citizen and given my country's history with Vietnam, that I would stand out like a bull in a china shop. But that wasn't the case at all. I found everyone to be very polite and friendly. The prison seemed to highlight the French occupation more than the US involvement in the Vietnam War.
I look forward to reading and commenting on your other posts and learning more about you and your experiences. All the best, Ira..