Why is this not true for elves, dwarves, halflings, goblins (a race that certainly looks diverse), or anyone else? If ever humans were ready to wear hats in a setting, BR would be that setting.
So I will ask, is this a PC’s are special situation, where if you did an elf campaign you might allow free floating bonus? Or allow Sidhelien to select either elves or eladrin?
Or is this a humans are special type of thing?
I’m perfectly happy to dispense with tropes and declare that all Brecht are not nautical guilders who are basically Han Solo variations who never abandon luck, wealth, and smuggling. But why then re-impose the trope of versatility on all humans? IMC, guilders wear their hat as lucky, merchant scoundrels, but actual Brecht you encounter often subvert the trope. Brecht nobles who are fighters on horseback, or scholarly wizards (Brecht wearing Anuirean and Khinasi hats respectively!) are common as encounters, especially when outside of Brechtur.
But as much as I like to subvert tropes, I don’t want to discredit them. While not all Brecht are rapier wielding rogues, they aren’t bastard sword wielders either. I don’t go from one of the lightest to one of the heaviest swords.
I’m not a fan of mechanical fixes that force tropes, but I’m not against them either. What I do not want is that elves, dwarves, et al are given mechanical hats and humans are mechanically versatile. I’d rather see Brecht have a +2 Dex and use that creatively (more than just rapiers) than see Brecht be “versatile humans” and select any bonus to create any character type.
The versatile human is a hat just as much as hard-drinking, honorable, miner is for dwarves. Its not a game balance issue, its a trope. You can balance Brechts against Anuireans, dwarves, and so on with the right advantages for each of the five nations.