Many "Classic" players want #nochanges. Classic+ would not be Classic and would only appeal to players who aren't vanilla-centric. Modern MMO players will want WOW TBC Gold modern designs, while old-vanilla players will want a simple design and would prefer "no modifications" because they are bad at the game...
Many players have switched to FF14 or New World so now they are expecting more or have just switched games. Classic+ must be more brainless than Classic to accomodate for "bad" players (LFR) which can only do Classic and on the other the other hand, it must provide contemporary games for all players... it's difficult to achieve, if it's even possible. Classic cheap Burning Crusade Classic Gold community is highly fractioned and it is extremely unlikely that it would come together to create a Classic+ version.