I don't think there is a plan that is set in stone for the future of the Calgary Flame's goaltending. Why would there be at the moment? We don't know how well Vladar is going to continue to develop, and we don't know how good Wolf will eventually be either. It is smart to re-sign Vladar for the next 2 seasons and provide that stability in net.
Then the Flames get options. In 2 seasons, Markstrom may be regressing or maintaining himself as an elite-level goalie. Vladar could be improving and may surpass Markstrom. Wolf's development may take a u-turn, or he may push himself right to the top as the starter. It really all depends on how all the goalies are doing. This buys the Flames a solid 2 more seasons' worth of stability.
Don't sneeze at the 'leftovers' either - Sergeyev is definitely worth keeping an eye on, and Chechelev may also pan into something. Calgary's goaltending is actually quite strong organizationally, which is fantastic for a change. Back in the Kiprusoff days, you had one glorious starter, and a 'B+/A-' level prospect you were hoping and praying would be ok, but never worked out. This is the first time there is depth in this position organizationally since I can remember - probably going all the way back to the Lemelin-Vernon days, and probably even better than that at the moment.