By Shawn Childs If the young tight end elevates his game, this offense could be a standout fantasy producer. The foundation of the Minnesota Vikings’ offense has a veteran feel, except for WR Justin Jefferson. They went 15-18 over the past two seasons with fading defense and a regressing offense. QB Kirk Cousins starts the year at age 34. The Vikings thought enough of his future to extend him through 2023 for an additional $35 million. The luster of RB Dalvin Cook and WR Adam Thielen faded due to both players failing to play an entire season in any of the past three years. The questions needed…