It's a legit criticism for BB's entire tenure for sure, but he has added "toughness" in the last year. The main additions of 2012 were JVR, McClement, and Ashton (plus maybe Deschamps if you count him as a main addition, which I don't). Throw in the pseudo-graduation of prospects like Frattin and Komarov and that's a fairly decent amount of toughness brought in. There's no straight wrecking ball fighter type, but so be it, it's not like Orr and Rosehill, or even the better versions of either, would've turned the tide in the Bruins slaughters. The team needed serious roster changes rather than a one or two player bandaid.
One of the issues kind of hiding the change right now is that the players those guys are designed to replace are under contract for this season. JVR over Mac. McClement over Connolly. Ashton over Lombardi (all kind of guesses, but about right). So while some of the less tough players have to move down the depth chart, they won't be replaced with your more prototypical depth/tough guys until '13/'14.
On D, it's basically only Holzer for Schenn starting and I agree I'd like to see a bit more jam back there, although I liked Franson's use of size as the season went on last year. He doesn't go Phaneuf or McCabe on guys by any stretch nor will he drop 'em to protect someone else, but he was using his size effectively, IMO. If Holzer and Franson could counterpoint Gardiner and Liles, there's a decent balance in the back-end. Still, replacing Schenn with higher end top 4 defensive d-man (basically what Komi was hoped to be) would change the dynamic of how the D-corps looks from a toughness perspective.
I don't mean to be rude, but I find the toughness debate is usually a foil for complaining about the lack of a heavyweight or the fact that Kessel isn't Gilmour or Clark. Both are true, but for some it's the end of the world and for others it's meh.
It's not like there've been all these opportunities to add the Lucic/Hartnell's of the world and BB's passed on them. Or even the Foligno/Clowe or Clutterbuck/Torres kinds of useful guys (putting them together the way I did isn't quite right, but I think my point is vaguely understandable). Would we really be happier if BB had given one of the ludicrous 4.5m deals last offseason to a Leino, Umberger, or Ladd kind of guy?
I'd say there's a legit criticism that he went against his prior successes with team building to try and fit with Wilson's style and he deserves criticism for how that turned out, but there has been a concerted effort to add, at the very least significant size, and hopefully toughness, in the last year. but these things take time and have to be done at the pace your payroll turnover allows.