That would be too much fun to start as a GM in the CHL and move up. Not explicitly as a structured mode itself, but to have the option of starting off as a GM in any league, and if you choose a lower one you are assigned a prestige rating commensurate with the league you are managing in.
This is all stuff that we've all been batting around here for years, but yes, it's time for GM mode to integrate all of its team and league databases into a playable format. It's the brilliant thing about FIFA's somewhat forgotten career mode.
There is nothing more fun to me than starting out in England's League 2, or some other low league like Ireland, or even in South America and work your way up to a giant club. The progression is infinitely more satisfying, and you experience a nice range of gameplay styles, environments, and end up with a genuinely enjoyable narrative.
Last year in FIFA I went form managing a half star team in the Irish league, to Norway, to Russia, to West Brom in the Championship (relegated), brought them back to the Premier League, got West Brom all the way to European football in the Euro League, and ended up getting offered the job at AC Milan.
So many amazing moments in there like the first game in a bigger league, first game in the Premier League, first time playing clubs like Chelsea and Man Utd after four seasons of managing, playing European football, and finally that first game in charge of one of the iconic brands of world football after seven seasons. The integration of leagues, and gradual progression added unbelievable depth and value to my experience.
Imagine starting as the GM of the Kootenay Ice and after a number of seasons in the WHL, AHL or Europe, you step into the GM office of and NHL team like Columbus, and then eventually the Detroit Red Wings, or the Canadiens, Leafs, etc...? Or, maybe you do so well you have a quick rise, or so poorly you are stuck exiled in Europe. Either way, it's an experience I'd like to have available to me after playing the series for 20+ years.