I think gear could work with a few things to prevent it from being mandatory.
The first thing is the actual gear dropped doesn’t need to be high level item. Higher than world content yeah, but not near raids or high M+ level.
Then tie Torghast into the great vault but don’t make it give extra item choice slots. Make it something like you can run either M+ or Torghast but don’t need both. So anybody already doing M+ for the week doesn’t need to run Torghast(and Torghast’s ilvl can be tuned so it’s not better than the group content but still decent gear).
Timers are a stupid way of enforcing a “GO GO GO PULL EVERYTHING” playstyle when you could have just made the content challenging without a timer and not care if somebody takes 10 hours to clear it because they’re being overly cautious.
Timers are one of the biggest reasons I don’t like M+ even though I used to love dungeons and wanted to be able to get near-raid level gear from them.