Something I really do appreciate with Chiltern's change is the re-timing of the Aylesbury-Marylebone via Amersham services. Currently, they're time to depart at xx18 & xx48, and the shuttle service from Princes Risborough arrives at the exact same time at xx18 & xx48 at many times of the day. After the change, the Marylebone services will leave at xx21 & xx51, allowing connection times.
Because I must say, having been on a service from Risborough and seeing a Marylebone service departing right at the same time as I'm arriving was quite frustrating! Also nice to see those services in themselves are going back to half hourly instead of the current hour gaps during the day.