St Louis forward core:
-Steen: 30 years old, career high 62 points (in 68 games).
-Backes: 30 years old, career high 62 points.
-Oshie: 27 years old, career high 60 points.
-Schwartz: 21 years old, career high 56 points.
-Tarasenko: 22 years old, career high 43 points (in 64 games).
-Sobotka: 26 years old, career high 33 points (in 61 games).
Those are St. Louis top-6 scoring forwards from this past season that will most likely be back next season.
Compared to Colorado:
-Duchene: 23 years old, career high 70 points in (71 games).
-Parenteau: 31 years old, career high 67 points
-Landeskog: 21 years old, career high 65 points.
-O'Reilly: 23 years old, career high 64 points.
-MacKinnon: 18 years old, career high 63 points.
-McGinn: 25 years old, career high 38 points.
I'd have to say Colorado's future is brighter given the age of the cores, matched success, and how the Avs already have 5 players with higher career totals than any player on the Blues. Tarasenko and Schwartz will undoubtedly close that gap though. Avs goaltending is also better, provided Varly can repeat last season.