So assuming that Samu, Valetini, Wright and Wilson are the four frontrunners for the extra three (including the bench) backrow spots, it's likely going to be one of the following variations:
6. Valetini
7. Hooper
8. Samu
6. Wright
7. Hooper
8. Wilson
6. Valetini
7. Hooper
8. Wilson
6. Wright
7. Hooper
8. Samu
6. Samu
7. Hooper
8. Wilson
6. Wright
7. Hooper
8. Valetini
I've bolded what I believe are the three most ideal options.
Valetini and Wilson gives you a lot of bulk, but no lineout jumpers.
Wright and Samu gives you plenty of jumpers and mobility, but too lightweight.
Wright and Valetini provides a high workrate off the ball, but no dynamic ball carriers.