But who the hells asked for Arcane Archer?

I mean come on ... basicaly any other subclass would be better pick.

Some of them would be limited by overall design/theme of the game.
Like, for Fighter; Cavalier wouldn't be doable with the design of the game. Samurai wouldn't really fit thematically. Rune Knight kind of competes with Giant Barbarian. Psi Warrior is basically Battlemaster 2.0 and Banneret is kind of boring.
So Arcane Archer or Echo Knight are the most notable options. Echo probably being hardest to implement (It also would end up feeling like an amalgamation of Trickery and War Cleric... Summoning a copy to manipulate the battle and gaining extra attacks)
Not to mention the fact that level 12 is the cap means a lot of subclasses don't get their most interesting features (Yes, they can bump some level 14 features down a bit, like they did with Draconic Sorcerer getting their Flight, but in some cases it can end up with the subclass not feeling particularly different to base classes until level 11-12) which can further limit how well some subclasses can be represented.