Expectations
Without any drastic moves, here's what I think Sweeney and management are aiming for:
Marchand - Bergeron - Heinen/Senyshyn/Stempniak
Vesey - Krejci - Pastrnak
Beleskey - Czarnik - Iginla
Vatrano - Kelly - Acciari
Chara - X
Krug - K. Miller
X - McQuaid
Forwards
Marchand - Bergeron - Heinen/Senyshyn/Stempniak: I think Heinen and Senyshyn will be giving a shot to make the team. If they aren't ready, I think they will sign Stempniak to a 1-year deal to act as stop gap for Heinen and Senyshyn.
Vesey - Krejci - Pastrnak: Pretty self-explanatory. Bruins are after Vesey and if they don't get him, Beleskey and Vatrano move up in the lineup.
Beleskey - Czarnik - Iginla: Spooner will be the Bruins main trade chip this offseason if Sweeney and co. expect the top 6 to look like it does above. I added Iginla here because the Bruins will be looking to add size at RW. I believe Colorado wanted to trade Iginla during the season, but Iginla refused to do so.
Because players with NMCs will need to be protected in the expansion draft even if they are UFAs when the season is over, it looks even more likely that Colorado will want to trade Iginla since they would have to protect him. They may be willing to trade Iginla for Seidenberg who they could use on defense and expose him in the draft which will free them an extra spot to protect a player. I figure the Bruins will need to add a young player like Morrow, Griffith, or Connolly to get it done, but I would do it since it frees us an extra year of Seidenberg's contract.
Vatrano - Kelly - Acciari: As stated before, Vatrano moves up if Vesey isn't signed. If that happens, I expect someone like Blidh to slot there. The reason Kelly is on this line is because we all know Claude has an unhealthy addiction to handedness as it pertains to our defensive pairs, but he certainly would not want to go into next season with 4 RH centerman. Yeah, I know, Claude being Claude.
Defense
Chara - X: Nothing new here. We've been speculating for a while which defenseman the Bruins should target. I frankly don't know, but I assume Spooner, Colin Miller, our 2016 1st, SJ 2016 1st, and the prospects I mentioned above that aren't traded will be used to obtain X.
Krug - K. Miller: I'm not enthusiastic about this pairing at all come next season, but I feel they believe this could be a solid 2nd pairing. Only time will tell I suppose.
X - McQuaid: X can be Liles, O'Gara, or Grzelcyk. I think the Bruins ultimately re-sign Liles because of Krug's injury and absence in the 1st month of next season due to his surgery. That leaves O'Gara and Grzelyck to compete for that 3rd-pairing job. If either O'Gara or Grzelyck impress, Liles will most likely be the #7D once Krug comes back. I also think Carlo has the chance to make the roster out of camp, but they shouldn't rush him. If he shows signs that he's ready mid-season in Providence, he'll definitely get a look because
McQuaid will be injured. But I wouldn't be surprised if at some point Carlo takes McQuaid's job next season, and hopefully Kevan Miller's in the near future.