What kind of Backgrounds?
It looks like the 5e Backgrounds we've seen so far are pretty generic and abstract (Commoner, Apprentice, Noble). They remind me of 0-level characters from the 1e Greyhawk Adventures book.
Wasn't the term "Background" used in 3e Forgotten Realms to cover the cultural homeland of each player? This was more specific and flavorful.
And "Background" was also used in WotC's Wheel of Time d20 game as the equivalent of "race" in D&D, to distinguish the various PC human cultures since there was only one non-human PC option in that game.
Will 5e Backgrounds fill all these roles?
If so, then I'd like to see 20 archetypal human cultural Backgrounds, with a brief synonymy for the various D&D Worlds which employ real world cultural features (Toril, Abeir, Oerth, Aerth, Ravenloft, Mystara, Birthright's Aebrynis, and to a lesser extent, Krynn). This would cover nearly all the Real World cultural flavors featured in those Campaign Settings:
Northman (quasi-Viking; Moonshae Northmen and Uthgardt Barbarians of Toril; Ice, Snow, and Frost Barbarians of Oerth; Antalians of Mystara; Rjurik of Aebrynis; also Ice Barbarians of Krynn)
Daleslander (quasi-Medieval English; Dalelands and Cormyr of Toril; Tharquish Empire in Oerth; Darokin of Mystara; Anuire of Aebrynis)
Ffolk (or Hillman or Highlander) (quasi-Celtic; the Ffolk of Toril [the name is parallel to real world "Tuatha"], Old Faith Oeridians of Oerth; Thratian Barbarians of Mystara)
Brecht (or Hattian) (quasi-Medieval German+Dutch; Hattias and Heldannic Knights of Mystara, Brechtür of Aebrynis)
Sylairois (quasi-Medieval French; Nouvelle Averoigne and Renardie in Mystara; from the name of the French language "Sylaire" in Mystara)
Kerendano (quasi-Medieval Italian+Spanish; Amn and Chondath in Toril; Caurenze and Espan Baronies in Mystara; the "generic D&D core" name is from Kerendas, which is the origin of both the Italian and Spanish cultures in Mystara)
Hordesman (quasi-Mongol; Tuigans of Toril; Tiger Nomads of Oerth; Ethengarians of Mystara, in Dragonlance: the Khanate of Khur in Ansalon and Uigans of Taladas)
Midani (or "Emirati") (quasi-Arab+Persian+Ottoman Turkish; Zakharans, Calishites, and Anauroch Bedines of Toril, Bakluni of Oerth, domains in the Amber Wastes of Ravenloft, Ylaris and Huleans of Mystara, Khinasi of Birthright)
Barovian (or "Eastlander" or Traladaran) (quasi-Eastern European; Rashemen of Toril, Stonefist Barbarians of Oerth, Traladarans of Mystara, Vosgaard of Aebrynis)
Katashakan (quasi-African; Chult and Katashaka of Toril, Touv of Oerth, Tanagoro of Mystara)
Rover (quasi-Native American; Anchorome natives of Toril or Abeir, Arapahi of Oerth; Atruaghin Clans of Mystara; also Plains Barbarians of Krynn)
Olman (or Anawakan) (quasi-Mesoamerican; Mazticans of Abeir, Olmans of Oerth, Azcans of Mystara)
Ossean (quasi-Aboriginal; Osse of Toril, Wallarans of Mystara)
Zindian (quasi-South Asian; Utter East of Toril, Zindia of Oerth, Sind of Mystara, Sri Ravji in Ravenloft)
Shou-jen (or Sufang-ren) (quasi-Chinese; Shou Lung and T'u Lung of Toril; Sufang of Oerth; I'Cath of Ravenloft, Ochalean of Mystara)
Ryuu-jin (or Nippon-jin) (quasi-Japanese; Wa and Kozakura of Toril, Nippon of Oerth; Myoshima of Mystara)
Milenian (quasi-Greek: Chessenta of Toril; Milenians of Mystara)
Khemite (quasi-Egyptian; Mulhorand of Toril, Erypt of Oerth, Aegypt/Khemit of Aerth, Thothia and Nithia of Mystara)
Maka'i (quasi-Pacific Islander; Makai of Mystara)
Untheri (quasi-Mesopotamian; Unther of Toril, Ishtarland of Oerth, Nimmur of Mystara)
As shown above, the core 5e names would be "genericized" by using an actual name from Oerth (or one of the other D&D Worlds) as the default. There'd be a table giving the name in other D&D Worlds which use Real World cultural flavors.
There are precedents for this: various Real World cultures were mentioned in the class descriptions of the 2e PHB. And these cultures were featured in the pantheons of 1e Deities & Demigods and 2e Legends & Lore.
These Backgrounds also form the cultural framework for other fantasy IPs: JRRT's Middle-earth, REH's Hyborian Age, Theah of the 7th Sea, and Warhammer Fantasy Roleplay.
These would be real, flavorful Backgrounds that players could get a handle on. If the Backgrounds are supposed to be open to all races then "-man" could be replaced with "-folk": "Northfolk". And they should be--depending on the campaign--since some D&D worlds already feature non-human races with Real World-inspired cultures--for example, the Aztec-style Orcs of Oenkmar in Mystara and the Mongolian-style Tamire Elves of the continent of Taladas in Dragonlance.
From this Real World-inspired base, many more Backgrounds--including "mixed" or invented fantasy cultures--could be featured in 5e Campaign Setting books.
This is what I'd like to see for Backgrounds in D&D Next.