Its hard to say for sure, but I think they are in a much better place to make the playoffs then not, especially when you consider their issues over the last few seasons. Numerous of their issues that were previously making them a bubble team per se seem to have been fixed.
The acquisition of Dvorak should be big. ex: he will improve their PP, PK, he's way more offensive than Danault, and he's likely good in OT, and be a shooter in any SO too. i.e. for several years the Habs were losing points stupidly, they had a bunch of games where they should have won but they ended up with 0 or 1 point. With Dvorak, they should win more of those games, so they should be able to finish several points higher than the previous years where they barely missed the playoffs. That itself should put them in the playoffs.
Similarly, the same idea with Allen too. Another big part of their bubble team issue was a lack of a decent backup G, and thats been fixed. i.e. they've had Allen for 1 season, and made the playoffs. If and when Price cant play they have a much better chance at wining those game with Allen then without him.
The Habs have had a crap ton of 1 goal games, that they've lost; along with tied games that they lose in extra time. A lot of those 1 goal loses should now be ties, and most of their tie games should now be games they win. Its not like every time they dont make the playoffs that they have been way off the mark. Usually, when they fail to make the playoffs, its only by 2-3 games. Dvorak and Allen should help them win numerous of those really close games where in previous years they lost those games and missed the payoffs by 4-6 pts.
Then there is the Caufield co-factor as well. He should be at a minimum a 30 goals scorer, if not close to 40 or more. Having him play for an entire season should also be a huge help to make the playoffs.