To me having ridden it a few times since the upgrade, the problem was their loading times are shocking. Wouldn't matter if you had 10 boats in the station, the one at the front still holds everything back. Even if you had a second boat waiting between unload and load, nobody can get in it until it moves forward, coupled with only being able to unload one boat at a time, unless the human element improves nothing else is going to make any difference at all.
Should have designed the new station to unload/load 2 boats at a time. Then it would have been 100% down to the park staffing it properly to keep the high throughput happening.