The only servers that do not allow Heroic are the progression servers that have not unlocked COTF . If you wanted a class change on a progression server then simply do so by making a level 1 and have at it. It would be different if the character is level 85 or higher on a live server and you wanted to change classes - then the Heroic is a feasible solution. Especially with all the free heroics they gave out last year.
Name change, no game mechanics impacted. Gender change, no game mechanics impacted. Race change, minimal game mechanics impacted. Class change, all game mechanics impacted.
It sounds like a logistical nightmare, but maybe it's easier than I imagine. For the epic alone, the system would need to do a check if your current character has completed the epic and which levels you've completed. Then it would need to delete the epics, whether they're in your inventory or placed in housing. Currently we can't use the new find command to find items we own that are in real estate not owned by us, but the class change would need to be able to delete the epics no matter where they're placed. Then all character flags relating to the epic process would probably also need to be removed from your character. I think the whole process could potentially put a lot of strain on the server. There are also a lot of decisions the developers would have to decide on about what would be removed and what would be retained. They'd need to do that for every class. It's likely that there's a lot of room for coding mistakes.
