I think it's hard to tell what's flagship and what isn't until we know how much each service makes in terms of numbers and profits.

For example, the X66 is probably one of GNE's busiest services and also one of the most frequent - but in terms of profits - I doubt they're high due to the number of passes shown when boarding, rather than fare-paying passengers. I think that's also why the X66 is so expensive - isn't it like £3 for a single?