The only change we made to our original plans is that we took out the clan city NPC reaction to the owners of the city regardless of race. This means that NPC guards won't attack racial enemies if they belong to the clan, and NPC vendors will trade with them. It makes sense that it would work this way, but the main reason we did this is in the spirit of player freedom, and not wanting to overly restrict player socialization for reason of race. This is not a game with factions as seen in other games. You don't have races with limited interaction or limited ability to interact. There will be one character race per world, so again this makes sense to us. Having said that:
All race clans cannot go everywhere as a clan. Certain members are always at risk of being attacked by racial enemies, and present an alignment problem to defend (see question 3 below).
There's concern by the community that mega-clans will form and own cities in all areas of the world. Size presents serious management problems, but also in Darkfall, the more you own, the more you have to lose. All things considered equal, a compatible race clan can have an advantage over an all race clan.