Six is an odd number to go with, but I can give you five. Fate/Zero, Madoka, Thunderbolt Fantasy, Psycho Pass and Kamen Rider Gaim all feature an idealistic woman who has one or more scenes where she's told how wrong she is and how dark and gritty the world is. They also all have a very cynical male character(except Madoka where it's a girl) who is the one telling the woman this.
There is usually a cynical vs a more optimistic character in Urobuchi's work, but the cynical one is universally
also wrong. In Thunderbolt Fantasy, Dan Fei is ultimately right to a large extent (in fact, the 3/6s of the party that initially seem incredibly unreliable all turn out to be on her side in the end, and the most unreliable looking party member turns out to be super-heroic, to the extent that his is at least his 36th time getting wrapped up in this kind of thing). Granted, this relationship plays out much more directly between Shou Yun Xiao (the cynical betrayer who dies awfully), and Juan Can Yun (the optimist who ends up getting married after finding out everyone else was worthy of his trust).
In Psycho Pass, the girl is, to a large extent, ultimately right. Madoka finds value in the magical girl system
even without fixing it and finds worth in sacrificing herself for a larger cause, adapting a lot of Homura's worldview while also growing far beyond the later as a person. Akane learns a lot from Kogami, but manages to do this while retaining a fundamentally positive view of the world, and continuing to be emotionally stable, rather than becoming 'clouded' like Kogami did. And, in making her peace with the world around her, able to chart a third path between blind acceptance and despair. Saber isn't allowed to develop as a character, but that has more to do with the fact that the plot demands she be ready for a character arc in the sequel that personal enlightenment wouldn't enable. In Gargantia, the optimist deuteragonist is more or less entirely right.
Even more notably, none of these characters are very similar in the notion of their optimism, Saber is a defeated hero whose seen her ideals shattered, even as she still clings to them. Akane is a young professional who wants to do good in the world, and feels respect and trust for society that she has to negotiate with reality. Dan Fei is the heir to a tradition that's left her sheltered from the world, but also committed to a specific cause and tradition beyond her. Madoka is defined by her uncertainty for the entire work. She's not finding her belief system wrong, but trying to figure one out in the first place. All of these are optimistic in ways that conflict with reality, but every character's optimism is quite unique.
Similarly the cynical perspectives ranges from a rejection of nobility in conflict to an oppressive Gesellschaft that impersonally categorizes and presses down on the protagonists to literally just a few assholes that really like swords. These share a similarity, but are more different than they are alike. Gargantia reverses the protagonist role, with the cynical, initially 'obviously' wrong, character being the PoV character, and the optimist being largely the one who proves them wrong, but Gargantia is kinda shit, so whatever.
Since being wrong, in these cases, is mostly fodder to develop as a character, we get "basically good protagonists that are given the chance to develop and have agency in doing so" (Dan Fei being the exception where the narrative is just really shitty to her, and her character development goes in a really awful direction.)
The 'depressed archer' in TB Fantasy isn't thinking he's right, and isn't particularly depressed, he's just an amoral asshole. In Psycho Pass, everyone uses guns, so this is not a valid trait to pin to a character. Mami... doesn't really turn out to be wrong persay to any extent, and the entire cast ends up fairly depressed. Also, Urubuchi also didn't do the character designs there, so I'm not sure he had much input on her using guns specifically. So, we have 'characters who use a ranged weapon' left, which is fairly bland as a descriptor.
"Heroes suffering because of idealism" is one of the most generic imaginable descriptions of most fantasy with heroes, and probably applies to most every heroic character who has some degree of idealism and sometimes gets involved in conflicts. Similarly, what else would a trickster archetype do if not lead people astray? That's basically a tautology. "A character that is, in some respect, a trickster appearing in some role in the story" is not particularly limiting as a theme, so neither of this really holds water as a repetition. More broadly, character development is usually a good thing, and changing your worldview largely necessitates it be wrong at the start and that you overcome adversity. If we have a fairly optimistic character, that usually means something about their optimism has to change. Final bosses are definitionally immense threats or they wouldn't be a primary antagonist.
Death of characters on the protagonists side in very violent works isn't unique to Urobuchi, or particularly notable as a theme or singular concept. It cuts a genre off in terms of lighter shounen, but mostly just establishes stakes (and doesn't happen in Fate/Zero or a number of other Urobuchi works).
So out of the array, the only ones that really stick as repeating themes that aren't absolutely endemic and true of most every actionish work of fiction are a fairly dark clash between an optimistic (often female) character and a cynical character, neither of who ultimately turns out to be right in the presence of dramatic and complicated systemic forces that transcend the immediate interpersonal conflict. TB Fantasy doesn't really fit this form, except that one of the supporting cast members has a positive outlook on life that isn't really disproven and doesn't really come into direct conflict with cynicism. These don't read as "the exact same character and plot points"
More broadly, even if you're right, working through the same themes in multiple works, at a broader level with significant genre and character diversity,
isn't actually a mark against an author. We don't say Poe was a hack because all his stuff was depressing, or Lovecraft was bad because everything he wrote just dealt with the humans being small in light of a vast, horrifyingly impersonal (and incredibly racist) cosmology. We don't call Arthur Conan Doyle a hack because he always writes mysteries. So many Greek tragedies playing around hubris doesn't mean the authors are hacks. Shakespeare's work ending in either death or marriage doesn't really disparage Shakespeare.
Writers are allowed to favor themes and ideas. The vast majority of actual great authors have pretty distinct styles and thematic concerns. Urobuchi obviously isn't among them, but 'repeating an clash between idealism and cynicism, neither of which can adequately answer to broader systemic \pressure without a synthesis" doesnn't actually feel like a bad thing to be stuck on.
Urobuchi's a mixed bag as an author, with a number of works that are fairly bad (Gargantia has some legitimately appalling moments for example,
though it's unclear how much of the trans/gay panic episode was Urobuchi's fault (ed: he didn't write those episodes at all, only the first/last), and stuff that's had his brand on in more off-hand ways has been awful (Aldnoah), but your criticisms are pretty transparently quite exaggerated.
