Cross facton guilds is the last faction divide hurdle. Once we cross that.. it makes me seriously wonder if there is a point to the story forcing the same races in only 2 factons.
I'm sure the horde and alliance can continue to exist, but we can have new factions, a 3rd or fourth even.. and this can change too.
Where a race ends up isi now pretty irrelevant, and world pvp can be entirely faction bsed whatever your faction as you will never lose the ability to guild and trade with your friends.
Proposal of changes: Some race re-organisation
Option 1
Character creation remains unchanged, players who pick a race now are joining a group of that race in the faction - htis is a lore change and doens't affect the current factions you play in.
In the story only: Many races have left the 2 factions, but soldiers and adventuerers who fought with them remian, meaning players will still be in the two factions but in the story: Night elves, Blood elves, Frosaken, Lightforged Draenei, Highmountain, Nightborne, Vulpera, Zandalari and Mechagnomes ALL go neutral. Joining Pandas and Dracthyr. Players must still choose which of the two factions to go into
Goblins are different, they are now available on the alliance as Steamwheedle Cartel Goblins.
Option 2:
New factions: Character creation changes to reflect this
Alliance, Horde, Ancients and Outcasts - the existing races are re-orgnaised into these groups. A player can choose to remain in the original factions or join a differnet one that his race is now in.
Changing factions to one your race is in is free. However you can moveyour race to a faction not allied with it, but you have to grind to exalted rep to do so.
Guilds exist.