Not sure where they could have rerouted the train? Only option would have been to move it further out, but that puts it right beside a busy street and and still would have had construction traffic to deal with. If COVID had not happened.... it and Tron would be up and running today. Yes looking back now, completing the entrance and the section needed to get the train operational would have made more sense. Really would have expected that to have been one of their first tasks anyway....
Most of what I've seen, says it's an exact clone of the
Tokyo Disneyland version.... so that's right around 1600 guest per hour. Which is in line with the other rides of this type at WDW. One good aspect of it being a clone, the attraction should not be plagued by operational issues like RotR is. But yeah I think you can count on it selling out pretty quickly for the first couple of years. Only saving grace is MK has a LOT more attractions than the other parks, and certain guest will prioritize other, calmer attractions for their family.