had a quick go

29.17, 2 br's, 10sp's

there are a few spots where I reckon you could get enough air to do a 3rd BR, but they're all incredibly difficult to capitalise on. I reckon you could with a right SS on the corner before the tunnel for the boost, and the same thing at the end of the last tunnel just before you exit - maybe. Could definitely get another br going on the right if you could pull it off there. But yeah... both locations would be next to impossible to nail.