I'm still trying to understand your stagnating part...
When Ziegler took over, he immediately proposed to absorb six WHA teams into the NHL, with Harold Ballard breathing down his neck. This was after a decade of rapid expansion in the NHL and the upstart WHA continuing to pluck players.
Within three years of his tenure, Ziegler was able to get the compromise: four teams from the WHA into the NHL. The issue here was stability. From 1976 until 1983, the league lost franchises in Kansas City, Oakland, Denver and Cleveland, while only gaining Hartford in the United States. Finances almost cost the league the Penguins and the Blues. If you think about it, that's pretty bad for a league that only had 14 teams in the US.
Let's remember that there were only three national TV networks in the early 1980's, and NBC ended their run of NHL hockey by 1975. The NHL was one of the early adopters in getting their national TV contract on cable, as truthfully, no one else wanted them.
The NHL finally did get on Fox, but that was when the networks realized they needed live programming in order to promote their scripted shows.
So after a long and tumultuous rebuild after the NHL absorbed four WHA teams, the league did set forth a plan for
expansion in 1988. But Ziegler could never get that TV contract. And I don't believe that TV contract was extremely important, either, as one can see that ABC/ESPN totally derailed the NHL in terms of a TV contract before the lockout.
If you think about it, Ziegler's tenure has been pretty much a mirror of the past dozen or so years, minus the WHA incursion. The game grew in the '80's and Ziegler presided over the San Jose, Tampa Bay and Ottawa expansions, and the stability was there. Fast forward to now, and the attempt is to stabilize franchises since the last teams were added, and the stabilization problem has been around since the beginning of the Expansion Era.
Let's face it. The League office is usually a mouthpiece for the collective individual members of the League, but the main responsibility is the ability for the League to shop rights for dollars. Ziegler couldn't do it well. Bettman did. And other than the fact that Ziegler was probably lying on a beach somewhere while Koharski was called a fat pig and not showing up for a couple of days certainly appeared that the League was leaderless.
There was only so much Ziegler could do. I honestly believe by canning him and getting Bettman the BoG put more power into Bettman's hands to do exactly what you have suggested.