Marsh has been really good at 3 and opening, he shouldn't be moved.Champions trophy is heading towards this at the minute I would say:
1. Head
2. Inglis (WK)
3. Green
4. Smith
5. Marsh
6. Short
7. Maxwell
8. Cummins (C)
9. Starc
10. Zampa
11. Hazlewood
Labuschagne, Hardie, Carey and Kuhnemann/Sangha would likely also go as a 15 man squad.
Everything is covered that way, Abbott could get in over Hardie for sure but I think Hardie can bat 3 through and bowl pace well, also Green and marsh bowl pace.
I really like Sean but I do think that Hardie has the better balance to a 15 man squad and I’m almost certain all icc tournaments are 15 men squads. You always have to bring a back up keeper despite it being annoying for balance.