I’m abit curious about your routing still and also a bit worried you might end up with some trouble. Once you choose to re-route the output of the second two to the first one - if you do this in the mixer like one would normally do - then outputs 2/3 go into 1, and if you by accident monitor in CR with the sources “latched” and select 1, 2 and 3, then you’ll surely get 2/3 twice: Once because they’re tapped in CR directly, and one more time because they also go into channel 1.
So I think this is a bit dangerous because there’s always the possibility that you re-route for export and for some reason forget to reset it, and then hear twice as much content from 2 and 3.
I would recommend that if you have enough monitor source slots avaiable (you have two more I think) then don’t do it that way. You could have three group channels with those three types of sounds and have all of them go to the main output, and then choose the three groups and the main output as your sources. That way you never have to re-route for export but still have all options available when monitoring.
I think that is ultimately ‘safer’.