To mix it up a bit, how about this:
1. Bula
2. Turuva
3. Doueihi
4. Toa
5. Staines/Naden
6. Galvin
7. Luai
8. Twal
9. Api
10. Hunt
11. Samuela
12. Seyfarth
13. May
Interchange:
14. Da Silva
15. Sukkar
16. Sione
17. Bird
When Hunt is gassed, move May to Prop and bring Bird on at lock (trying to reignite his creativity as a ball playing forward).
The 2nd interchange is Twal for Sione.
3rd is Sukkar for Seyfarth..
It means our rotated forward pack would be:
May
API
Sione
Samuela
Sukkar
Bird
You could then bring hunt back on for Bird, and push May back to lock.... As Sione gets gassed, replace him with Twal.
This strategy would need work during the week at training though - how May would switch in attack and defence, in and out of the #13 role.. Bird is also a pretty handy ball player on his day and can shift into #13 when May is at prop..
I just think we are wasting the 13 position with Twal there, he isn't a ball playing forward, it isn't his fortae.
Not saying this is the best idea ever, but I think we are missing a creative link in the forwards....