What about a 'TALES OF ASGARD' prequel tv series for Disney+ with Heimdall, Lady Sif, Volstagg, Fandral, Hogun and Balder (new introduction) as protagonists in order to give justice to these characters? :
ODIN VALHALLA RISING
MCU: Heimdall VS Lady Sif - Battles - Comic Vine
Sif (Character) - Comic Vine
Heimdall | Who's Who
Hero Spotlight: SIF [Vid] - Player Guides - Empires & Puzzles Community Forum
Thor: The Dark World (2013 movie): What happened to Heimdall at the end? Wouldn't he be able to tell that [x fact]? - Quora
In Marvel Comics, who is more powerful in Asgard, Lady Sif or Valkyrie? - Quora
Legends of Asgard - The Rebels of Vanaheim (Heimdall Trilogy #2) 9781839080784 | eBay
Heimdall | God of War Wiki | Fandom
New GOW Ragnarok Image : r/GodofWar
Sif | Marvel Cinematic Universe Wiki | Fandom
Why did heimdall look so upset when he caught the arrow? : r/GodofWar
Heimdall | Megami Tensei Wiki | Fandom
In Thor Comics, Lady Sif is Actually Heimdall's Sister
Who would win, Sif with weaponry (MCU) vs Heimdall with weaponry (MCU)? - Quora
Thor: 10 Cool Things You Didn't Know About Sif
The Rebels of Vanaheim: A Marvel Legends of Asgard Novel (paperback) 9781839080784 | eBay
Who is Marvel's Heimdall? Powerful All-Seeing Asgardian - YouTube