New instances and other things are essentially retail. It's basically creating an "alternate timeline" where you add things to the classic timeline that WOW TBC Gold aren't already available in retail. .... I understand rules changes, etc. However, adding bgs/areas. is becoming a retail-oriented thing. ....
The people who say that classic+ costs too much are naive. One commenter suggested that it might cost hundreds, or even millions. Do you smoke? They have a reliable platform that is suitable for traditional. The WoW version that is vanilla has a large amount of information. It will cost just hundreds of millions to include an entirely new zone, classes modifications, and a global boss. The classic game from Blizzard was a huge financial success. Take a look at the massive server issues at the time of launch, and the twitch figures. Seasons of Mastery will not attract many more gamers to WoW. Classic+, however, is a great option. Today, RuneScape's classic school continues to be used by new players. Even though it's an older game and players aren't convinced that buy WOW Classic TBC Gold they're wasting their time.