Wanted to provide an update here to help those looking to head to carnaval in the future
We had fantastic time. Rio is without a doubt a magical place. The people were friendly and respectful. I must have gained 10lbs on the Caipirinhas alone.
We never felt unsafe or uneasy, but we dressed as casual as possible. I had my phone on me at all times, but made sure to only use it when I was aware of my surroundings. We used Uber to get around and never had an issue. We took the advice upthread and only used ubers with a sizable amount of rides under their belt.
We had a chance to visit most of the locals in the city. We even found ourselves at a bloco in Lapa. Not saying it's safe place overall, but we never felt it was dangerous to be there.
The JW Marriott is a perfect jumping off point, and it's proximity to Copacobana Beach was very convenient. It's not the lap of luxury, but we were very happy with the property. Staff is exceptional.
My girlfriend and I attended both the Copacabana Palace ball and a camarote for the Samba parade (Rio camorote). What an incredible experience. The Samba parade did get pretty repetitive, but it was great fun to the early hours of the morning. Both events were pricey ($500 a ticket) but worth the splurge. If I had to choose one, I'd personally go with the ball.
We are already booked to return next year, assuming the event remains
If anyone has specific questions about my experience, would be happy to share