I am not comfortable with the quality vs. quantity argument.
First, you need more than four draft picks every year to have enough players on the team who are legitimate starters in the NFL. You can find in rounds three and four tight ends, running backs, defensive tackle, linebackers, safeties. We have seen in recent years the limits of relying so heavily year after year on undrafted free agents.
Second, the number of players a team has playing under their rookie contract, the better a team's position should be relative to managing the salary cap.