Individual B decides to start a new character, he logs into the game and immediately begins to quest. He gets to level 4 and his bags are already full. He goes to the merchant to buy new bags but can't afford any. He sells all the junk he looted that slowed down his leveling and still doesn't have enough. As he levels to 100 he is also short on gold for other things that would make leveling easier, such as mount training.
The expansion is set immediately after the events of Legion. Two continents have been added within the Great Sea between the Eastern Kingdoms and Kalimdor: Kul Tiras, one of the major human kingdoms, and Zandalar, the homeland of Azeroth's trolls. While the Alliance and Horde will initially travel to one continent respectively, both continents will be available to both factions at level 120.
As for Battle for Azeroth’s lack of new 120 talents, Hazzikostas explains it as a tough scenario. If the designers come up with three new abilities for rogue or death knights, those classes may not necessarily need three new abilities. Those abilities may be filler, or they may shore up a weakness in the class design and remove counterplay. That being said, Hazzikostas does agree that “it’s possible we’ve gone too far.”
You will need to cover very large areas in order to get a few chests as they are quite rare. Vanilla, TBC and WotLK zones work best. The way I like to do it is to park one Rogue class trial in Outland and one in Northrend, then fly over the whole continent and look for chests. One whole run might only yield 3-10 chests but you will still make a bunch of gold as you are almost guaranteed rares in chests in these zones.