Without further personnel moves. I do believe there is room for improvement with the current roster provided the right direction and systems are provided by the new staff.
One, figure out a way to get more offense out of Berggren, Veleno, Kane, Tarasenko, and Compher. Those guys are capable of providing it, they've done it in the past. To watch the Wings offense this season it just feels so stifled, it goes beyond losing Ghost, Fabbri, Perron, and Sprong. I think it's legitimate to wonder if the directive from Yzerman to be better defensively caused Lalonde and Boughner to focus the system and players so strictly on defense that it killed their offense. The Wings look slow and create NOTHING off of the rush, and I believe a lot of that can be contributed to demands in defensive play. The Wings have worse GA results than the defensive systems deserves simply because the Wings are playing in the defensive zone 70% of the game. Every team in the league would have terrible defensive numbers if they spent that much time defending and not playing offense. If McLellan can figure out a better way to balance the offensive/defensive demands, then this roster will look better on the ice.
Two, get the role players to be physical. This could be a tough ask. It's an element that has been sorely missing from the Wings' play since the days of McCarty, Draper, Maltby, and Drake. Rassmussen, Copp, Fischer, Veleno, and Motte need to make the game miserable for the opponent. What that means, is to be on top of the opponent to a frustrating degree and to HIT with a PURPOSE. No more just bumping into a guy and thinking you're hitting someone. No more skating at a puck carrier and then peeling away once the guy passes the puck away. It means hitting to dislodge a player from the puck, hitting to knock a player out of the play, hitting to make the player feel it. When opponents hit Larkin, Raymond, Debrincat, and Berggren they're getting knocked down and knocked out of the play. They take a LOT of abuse on a game-by-game basis. That is NOT happening to the Wings' opponents. It is beyond time for that to change.
If McLellan can get these two things worked out, then this team could improve without additional roster moves. I do believe that the personnel on the roster is better than the current results. We'll see how much better.
On Rassmussen, in particular, for as much as I rag on him and think he's a total disappointment for what he brings to the game, I would tell him that he has an opportunity for a permanent (or, as permanent as things can be in professional sports) role in the Top 6 provided he understands why he is there. And the why is to be a physical bastard to play against. You hit everything that moves and hit it hard. You dig for pucks along the boards and then go plant your ass in front of the goalie. When someone crosschecks Raymond in the lower back, you fight that guy. When someone boards Larkin, you fight that guy. When an opponent is taking runs at our guys, you fight that guy. End of story. You do that and you'll keep being put on the ice. Don't do that and you are of no use.
Last thing, I know a lot around here a really down on the roster itself, but I'm going to place a little more blame on Lalonde. From what I have been told from the locker room, the team is in a pretty dysfunctional state right now. To end the year last season and through training camp this season, the team was in a really good spot. When the start of the season began as rough as it did (the offense being non-existent. Losing games) the team has started to fracture. Not due to personalities but because the players are frustrated and disappointed in the lack of success. Where this comes back to Lalonde, is that as the locker room is struggling, the coaching staff was keeping with the "everyone stay calm, stick to the plan, things will come together" message even though the players saw that that wasn't happening. The coaching staff was bringing no intensity and players were playing like it. A swift kick in the ass, some intensity, and real demand for performance will go a long way with this group.