Without at least some starting experience. That doesn't sound like tons of unknowns.
Bolles should be rock solid. Utah actually moved the OL around to accommodate him. So that's not a bad sign.
Fulks is a new WR. That's an unknown as is the quarterback. But coaches are excited about both guys. I trust their instincts.
They lack explosivity. The biggest unknown is how well they'll take care of the ball. But it's not too much to ask to equal the same output as last year. Especially the last few games.l without Booker.