1. When you transfer (event or bib), it auto-selects the team of the original registration. It also properly handles team size caps when you are transferring for a team that is full.
2. An option on the team type setup to disable captains from adding and removing members. It also has an option to allow captains to remove those who registered with special group pricing. This will remove them from the race (unlike when an admin does it).
These options are int he Advanced Settings of the Team Setup and can be done per team/group type: