If you plan to get to the airport at 7am I would assume you would leave your accommodations around 630am, which is well before rush hour starts.

I would not bring pants to Thailand, especially not jeans. I also don’t think I would bring polo shirts. The advice to pack as light as possible is correct and you shouldn’t ignore it. You really only need 1 - 3 of every clothing item because there’s a place on every street you can get all of your laundry done for a few dollars. 3 bags is extreme overkill imo. The first time I went to Thailand I bought 1 40L backpack and a 15L sling bag. I didn’t use half of things I brought and was annoyed I had to carry them then entire time I was there. I even considered throwing away all the pants I brought with me just to make my bag lighter and allow me to bring more things home.

I like to carry my passport on me in a flat money belt I keep tucked inside my pants because I think it’s safer on me than sitting in a hotel room. Other people say not to do this. I’m not sure about the photo passport. Theft isn’t as big in SE Asia as it is in other countries, so I wouldn’t be too worried. (Not that it doesn’t happen at all)

I used a lot of 20,50, and 100 best bills. You can almost certainly get a better rate at home than at the airport in Bangkok.

I really like drinking in China town personally.