That team did rely on miracle comebacks. But it was also the 5th highest scoring team in the NHL with offensive contributions from the backend allowing less skilled players to produce playing a simple game, and it also had barely-average NHL goaltending with Hiller and Ramo both letting in their share of soft goals but just good enough to win games. It absolutely had issues, but it had legitimate strengths that were tossed out the window when Gulutzan came on board. In fact the 2014-15 Flames had a +25 goal differential.
As to your other points:
1)Were the Canucks really the "perfect" first round matchup, or is that revisionist history after Hartley coached circles around Desjardins? They were a 100 point team, with most of its roster healthy. They were predicted by most to beat us:
7/12 espn writers picked the canucks
NHL.com even had an article about how the Canucks would win the Cup.
I'm sure I could find more. In general few thought the Flames drew an "easy" matchup, although obviously Anaheim would have been a difficult matchup.
2) They got dusted by the Ducks, and yet still won a game, which is more than can be said about them from last year. And they didn't have Giordano or Ferland in that playoff series(or Hamilton, or Hamonic, or Stone). The Flames now SHOULD be much better than that team, but it's not clear at all. If anything, if the 2014-15 Flames and the 2017-18 Flames were to meet in the playoffs, the Flames would be the "2014-15 Canucks" of the matchup. That team was not remotely a contender, yet they pulled every stop to get the most out of what they had. This current team arguably gets the least out of what they have, even though they probably "should" be a contender.