A quick update:
- I cleaned the TB
- ATF level is perfect
- I added dry gas and a few gallons of gas in the tank
I drove about 20 miles around town tonight after cleaning the Throttle Body, and I experienced the hesitation/surging on two different occasions. Both were going uphill, and in both cases it was after hitting a bump. There's one spot were I can reproduce the issue pretty regularly, I'm thinking about investing in some OBD datalogging software to try to capture some of the data stream while the issue is occuring to review later.
Here's the before and after for the Throttle Body cleaning: