Medium across the board for me at 5’10” and 11 stone and a bit (178cm & 72Kg).
Don’t just go up a size on Castelli kit. If you are buying a Castelli Gabba or Free Aero Race bibs then they are going to be pornographically snug. They are meant to be the equivalent of a skin suit as they are race wear. If you go a size up for comfort off the bike then they are not going to fit you correctly on the bike.
The fit difference between Castelli ranges reflects the intention of the kit. The race stuff is super tight and gets more forgiving as you move away from the aero focused kit.
For me Rapha tops are too long on the chest and once you are down in the drops the zip will ruffle up unless it is a quarter length zip. I have a short sleeve club jersey which is a really nice casual ride top but my pro team jersey fits well stood up but ruffles awfully on the bike. To be honest I have worn it a handful of times only as I’m embarrassed to be seen in it. I think Rapha stuff is cut for a more upright position so if this is more your style they may fit.
Even Rapha’s own promotional material shows the problem;