I have a number of thoughts:
1) I don't think Plaxico fits here. Quite simply, unless there's an injury, I don't see him playing here. Gronk, Hernandez, Lloyd, and Welker should be in for 85%+ of the team's offensive possessions next season, which leaves one spot for running back or a fifth receiver. Considering that we'll often have a RB on the field, that leaves very little time for Plaxico. And I'm not so sure a guy like him can handle so little PT. Just look what happened with Ochocinco. I'd rather keep guys like Gaffney and Stallworth who know the system. They'll be much more likely to fit in and be ready for a larger role when called upon.
2) Offensive line should already be better next game with the return of Mankins. As long as Vollmer is healthy by the time the season starts, I think we're fine with Solder at LT, Mankins at LG, Vollmer at RT, and then either Koppen at C and Connolly at RG (that's where he started last season before Koppen got hurt) or Connolly at C and either Wendell or Cannon at RG. Water would obviously be huge, but as long as Vollmer and Mankins are healthy, I think we'll be fine. Remember, Koppen and Connolly were both starters opening day last year.
3) I don't get the whole fullback thing that McDaniels is doing here. Besides being a dying position in the NFL, it doesn't seem to make sense to carry any of the guys we have from a talent position. I think the much better idea, and perhaps what they'll ultimately do, is continue to play Hernandez and perhaps even Gronk, in the backfield in a fullback position. This does a variety of interesting things. Not only is it hard for defenses to read, it also is a way that the Pats can carve out more time for 3 receivers will still having someone in the backfield as a blocker. I also like Gronk as a lead blocker from the backfield with either Ridley or Vereen. I just don't see how Kettani or Larsen are really going to be an asset when we could keep an extra player someone else and just let the TEs do it.