Yeah nobody expected Tampa to miss playoffs in 2017, and they did. These things happened. Dallas made final a year ago, then missed. Nobody expects them to, but it's not exactly impossible. Atlantic is also difficult:
1. Montreal just went to finals. Maybe they struggle for reasons known, but maybe they ride that wave and are a top team in divsion
2. Toronto should be a top team in division. Playoffs may be difficult, but they'll do good in regular season
3. Boston won president's trophy 2 years ago, still very good last year, should be again
4. Florida was very competitive last year, could be so again. Imagine if Bob actually bounces back?
5. Metro is arguably even harder than Atlantic, and could land 5 playoff spots themselves.
I'm not saying Tampa is likely to miss - but if they go through a bad stretch for whatever reason (likely injury) - it's likely to be a very competitive year in the east to make the playoffs, so even just one bad stretch could tank a team.
Buffalo making the playoffs....no. I thought they'd be more competitive last year, and they got worst, by a lot. And as I just laid out, Atlantic + Metro will be very competitive this season. I can't imagine Buffalo makes it.