There's other factors that could swing things.

• Retzlaff takes a major step forward in his second year
• Woods fixes the OL issues
• Multiple of the young, unproven, but well -regarded, guys (Hagen, McKenzie, Swanson, Bowers, Asiata, Bamba, McKenzie) break out
• Pass rush greatly improves with Bagnah and Batty in their second year with Hill
• The secondary (and the rest of the team) stays healthy

There's definitely paths to upside for this season. This is more me saying that I get why Vegas is down on us. Each of these improvements relies in something that hasn't really yet been evidenced. 

They're all possible, but Vegas is leaning to the most likely case. As fans though, we know that upside exists, and if more of those things go our way then expected, that's how we beat the expectations