Have 49ers improved? Analyzing defense, special teams

Jim Harbaugh has several go-to inspirational sayings.And one of them greets players as they walk from the locker room to the practice field at the 49ers' Santa Clara workout facility. (And I noticed last week that it's plastered along a fence on the Stanford practice field, too.)You are getting better or you are getting worse. You never stay the same.With that in mind, let's take a look at whether the 49ers have improved, position-by-position, with their pre-draft moves.First, we'll look at special teams and defense:Special teams: It was important for the 49ers to bring back return man Ted Ginn and C.J. Spillman, their best player on the coverage teams from a year ago. Free-agent pickup Rock Cartwright replaces Blake Costanzo as a core special-teams player. It's difficult to imagine that 37-year-old kicker David Akers can be as good as he was a year ago, but the 49ers are hoping to settle for fewer field goals, too.
Bottom line: Slight dip because the bar was set so high.Defensive line: Everybody is back from a year ago. It's easy to make an argument that Justin Smith was the most valuable defensive player in the league. And nobody on the team works harder than Smith. He transitioned immediately from the end of last season into beginning his preparations for 2012. He enters his 12th season, and he has to start slowing down at some point. Right? Ray McDonald is entering his prime, and Isaac Sopoaga should be able to duplicate what he did last season at nose tackle. The 49ers did not get much from the backups last season. There should be improvements there. Some combination of Ricky Jean Francois, Demarcus Dobbs, Ian Williams and Will Tukuafu should win the confidence of the coaching staff to find spots in the rotation, thus ultimately making the starters more effective.
Bottom line: Slight improvement.Outside linebackers: General manager Trent Baalke made it clear that the 49ers expect Aldon Smith to be an every-down player in 2012. He played just 48.2 percent of the defensive snaps a year ago. That means Parys Haralson, who played almost exclusively in base downs last season, is currently a backup. Ahmad Brooks returns as an every-down player on the other side. He was hungry last year in a contract year. Now, that he has signed multi-year contract, he has to play with the same urgency. It's a good sign that he's hanging around the Bay Area and working out at the team's practice facility.
Bottom line: This could be an instance where the 49ers take a small step back to move forward, as ultra-talented Aldon Smith will be learning to be an every-down player.Inside linebackers: Patrick Willis and NaVorro Bowman were first-team All-Pros last season. Willis enters his sixth year, and is entering his prime. Bowman had a breakout season. Top backup Larry Grant is unsigned as he remains available on the market as a restricted free agent. Bottom line: Yes, Willis and Bowman will be even better as the starters, but depth is a question.Cornerbacks: Carlos Rogers and Tarell Brown are back as the starters, with Chris Culliver and Tramaine Brock as the backups. It's difficult to believe that Rogers, as an eighth-year player, can be much better than he was a year ago. But Brown, Culliver and Brock should improve with a full offseason of work.
Bottom line: Improvement.Safeties: Free safety Dashon Goldson was tagged as the franchise player, and strong safety Donte Whitner is back for his second season. Behind the starters, the 49ers have nobody who played a down from scrimmage. Reggie Smith is testing the free-agent market, and the team has not placed a high priority on re-signing veteran Madieu Williams.
Bottom line: Slight dip, based on current lack of depth.