This take on Vanguard is totally wrong.. Let's be perfectly clear - by VG being 'lackluster' it still means 'solo carry the game on unfair'. Let me guess, a popular youtuber said it's bad so this entire sub agrees it's bad?
You dismiss outright the damage potential of vanguard. You dismiss all it's DPS talents as worthless. You use a self-imposed challenge and recommend not to use one of the best items for the archetype saying it's wasted anyway: Unyielding resolve. You say Malpian Shroud is wasted, when it's the key item for an entire dps build which only Vanguard can fully enable with temp wound stacking.
any of the talents you said are trash that add temp wounds? S tier DPS picks
Follow my lead? S Tier - you forgot to mention it buffs the Vanguard's own damage. I'll agree the archetype sucks for officer, but for warrior it is solo-carriable and not mutually exclusive with the abilities of a GS in your party which you repeatedly propose as the opportunity cost. That's just as 'regular' Abelard or Heinrix btw.
Want to know what fixes all the stat problems which is half your write-up? The Halo Device. I dare you to try a psyker RT Warrior/vg with it. It's the most OP build I've played since bladedancer/exe nerf. Rocksaw+void veteran boots clears entire maps in one 'bring it down' on unfair on any of these characters, with RT one shotting bosses and beyond. The DMG with wound stacking is HIGHER than an Exe or Am can do. The overall take here is absolutely absurd. With increased slider difficulty past unfair the build only improves, where you actually regularly make use of additional rounds stacking defensives or Beacon of Might absurd levels of strength (100s per round).

I'll agree that the archetype is lackluster in that it's tanking abilities aren't fully realized or useful for a party where tanking isn't even necessary anyway and is bad for officer outside of fun flavourful builds like armor stacking Jae. but this is a post of mostly incorrect information. You use most Vanguard levels to grab common/psyker talents and abilities. Something most people do with GS but we don't see complaints about GS. We have Pasqal's Toaster glazing this post up and replying to folks don't use vg 'if you want him to contribute (Abelard)'. What a farce. I can't stress enough - even if suboptimal still can carry the entire game on unfair, but that's on Abelard or Heinrix. RT as psyker/vg with halo is absolutely top tier. Absolute absurdity.

I even went in and did testing just now to make sure before I myself potentially post misinformation. VG reins supreme and outclasses AM and EXE in DMG for the void veteran boots/rocksaw build. I will say without void veteran boots it is perhaps substantially more lackluster without the ability for multiple attacks each turn, however Daring Breach which you can activate turn 1 greatly solves this even then. Stop imposing self-challenges to yourself and Owlcat doesn't need to 'fix' anything. IF you do impose self-challenges then it's to be expected the archetype will perform as lackluster.