Understandably as a live service game, no new content could mean a death sentence.
But there comes a point in the (theoretically) infinite march of a perpetual beta where older pieces of content become so obsolete that it feels pointless to consume said content. One example being Hydroid. His entire thing, that is, AOE lockdown and looting, has been totally outclassed by Khora.
So my vote goes to revisiting older pieces of content. Reworks, polishing, the works. I mean fucking hell, look at Yareli. My favourite frame. 2 years in, still riddled with bugs. Gameplay-breaking bugs mind you.
Also hoping for reintroduction of Raids.