It's Martin St.Pierre, Nick Tarnasky, and almost certainly Michael Blunden on waivers for the Habs. Good chance of Gabriel Dumont as well... he's close, and in some seasons could have made the team, but he'll need a little luck to make it this year... likely in the form of injury recovery time should players like Parros or Gionta need additional time on IR to start the season.
On D, a guy like Davis Drewiske will have to watch himself... the Habs do have Tinordi (and to a lesser extent Beaulieu, and to an even lesser extent Pateryn and wildcard Nygren) pushing for jobs. But at the end of the day, if the Habs go with 7D instead of 8D, then the reason they re-signed Drewiske was that he's a guy who can handle being that #7/8 guy, and can step out of the pressbox when needed, will conduct himself professionally in the meantime, and is also very cheap on the cap. Meanwhile, they will not want their ace young D prospects like Tinordi or Beaulieu sitting in the pressbox - big minutes in Hamilton will suit them more. So Drewiske would have to really mess things up in camp to get waived. He may be at risk later if Emelin comes back and somehow all the other D are healthy.
That's about it. I interpreted Dustin Tokarski as waiver-exempt from his birthdate/pro start, but he also has his 4 years, so maybe he's not, and I'm not looking it up. If he's not exempt, he's on waivers too.
Risto is already signed, so I expect him to get a 9 game look. The front office have been talking up Zad quite a bit, but, I think it will vary depending on how he does in preseason games.
Zadorov is absolutely nowhere near NHL ready and if buffalo puts him in the NHL this season they will ruin him. I'm higher on this kid than most. I think he's a fantastic prospect. I'd have taken him before Bo Horvat. He's not close to the NHL.
There's pretty much a 98% chance Steph Da Costa hits waivers. He's looking very good in Sens camp and I think if there's any team out there lacking skill down the middle, he'd be a very good pick up. Sens just can't accommodate him. Really good upside and he could be a second line guy in the near future.
EDIT: Can the Oilers accommodate him on their roster with RNH out? I know they already lack size but he'd mesh well with guys like Yak or Hall. He's a great passer.