I'm finding that this works better for me, using a different /target line for each toon based on a 'chain of command' logic:

1IC: (blank)
2IC: /target [target=1IC, nodead, help, exists]
3IC: /target [target=1IC, nodead, help, exists]; [target=2IC, nodead, help, exists]
4IC : /target [target=1IC, nodead, help, exists]; [target=2IC, nodead, help, exists]; [target=3IC, nodead, help, exists]

Where 1IC is the main toon, 2IC is the second in command, 3IC is next and so on.

Thus the line above replaces the word TARGET in the follow macro, making each toons macro different:

TARGET
/follow
/stopcasting

This has one advantage over using 'target [target=Party1, nodead, help, exists]; [target=Party2, nodead, help, exists]; [target=Party3, nodead, help, exists]' or similar named macros because you will not get whoever is in command following the 1st remaining party member when the 1IC pops their clogs.