Saying "All sword-school bards are wandering minstrel types." or "All valor bard characters have a skald-type concept." is something that you seem to have implied that you're doing, and what we were concerned about.
That is where we're wondering about the agency of your players to determine their own concept.
The player gets to choose a culturally appropriate archetype, determine the background and goal (within in terms of the setting and the culture within where they grew up although the goals can change as they adventure and travel).
Part of what I want to do is develop specific archetypes from specific influences from historical cultures, myths, and movies that fit the setting that I want to create. There may be multiple ways to approach a concept, but I am the one that determines what best represents it both thematically and mechanically for the campaign or a culture not the player. In the process, this means my eliminating specific approaches that might have been been introduced over the editions 2e kits, 3e prestige classes and 4e including the idea that players can reskin as they see fit. This is no different than Gygax writing in a non-Dragon article that Robin Hood based characters should be done with either the Archer or Bandit class from Dragon classes rather than using the Fighter, Ranger, or a Rogue (he might have also included a hunter class that he wrote elsewhere as an option for a Robin Hood character, but I don't recall).
I am not saying that I don't allow multiple ways of approaching certain concepts. For instance, wandering minstrels in the campaigns that I run and they can be handled in multiple ways. They classic minstrel might be a rogue proficient in a musical instrument (and, maybe, history) and even a third party subclass that I am allowing. They might be also be a light armored warrior proficient in a musical instrument (and, maybe, history) and then take a third party subclass. Characters with another class that plays an instrument n might call themselves a minstrel. Any of these might also call themselves a bard or skald depending upon their culture or knowledge of the term from another culture. However, true Bards and Skalds will come from specific cultures and use the Bard class along with specific subclasses (and some tailoring of the original class). Similarly, if some rogue wants to pick up a short sword and dagger, use acrobatics, and call themselves a swashbuckler, that is fine. A fighter battlemaster can choose an appropriate fighting style, appropriate maneuvers, acrobatics, and choose not to where armor (or only light armor) and call themselves a swashbuckler. In either case, the player can discuss it with me along with the character's background to ensure it is logical for the setting. However, someone wanting to be rewarded with more benefits mechanically is taking Khaalis's light fighter class variant and an appropriate archetype whereas I am not going allow the official Swashbuckler rogue subclass as I don't like it mechanically and consider the Light armored Fighter variant as a better representation of the archetype. The same would hold true for Corsairs and other light armored fighter types.
