The keys to the Red's defensive improvement are Suarez and Peraza.
If they're league average or better, the D will be fine.
Not elite, but good enough to let the best hitters outslug other teams.
Williams' bet is that his team of 7 100+ wRC+ bats, the pitcher, and Barnhart have more chances to impact the game than opposing teams who play 5 - 6 100+ wRC+ sluggers and three or four fleas.