Update: The reason for less experience from gathering is due to how Blizzard revamped professions and broke them down by expansion. In order to get full exp from gathering you'll simply need to find a profession trainer for the relevant expansion. (WoD you just mine or herb the first one ypu come across and the game gives you a scroll for learning WoD gathering).
The expansion brings a major change to the PvP ruleset on each realm. Every realm by default only allows players to attack NPCs in the open world; players who wish to engage in world PvP now have a setting called "War Mode" that can only be toggled on or off in their faction's capital city (i.e. Stormwind for the Alliance and Orgrimmar for the Horde). While in War Mode, players have access to new talents and abilities, as well as a slightly accelerated rate of XP gain. Characters with War Mode activated are only able to see other players with War Mode, unless in their own capital cities.
Obtaining Items from the Black Market Auction House Everything about the Black Market Auction House, including unique items for sale, how to place bids, and where to find the Auction House. Professions in Battle for Azeroth Professions in Battle for Azeroth, the next WoW expansion after Legion, have received a significant update, with many new recipes as well as a significant skill squish. In this overview, we'll highlight the major recipes, reagents, and useful items each profession offers. Obtaining Blizzard Shop and BlizzCon Vanity Items How to purchase and collect all of the mounts and pets from the in-game Blizzard Shop and special promotional events like BlizzCon. Obtaining All the WoW Trading Card Game Items Learn all about the quirky Trading Card Game items, from spectral mounts to weather machines, as well as look-alike items that are easier to obtain.