1) If people currently don't want to run dungeons - then no change. You may get lucky and see that out of the newcomers, players still want to knock out dungeon quests. (A full BRD run with all quests is one hell of an exp haul)
2) Questing in quest greens is a perfectly normal thing - and always has been. Killing mobs in quests greens is normal. Killing mobs in dungeon blues is just easier. Not game breaking.
3) If a player wants to neglect their professions while leveling - they will. Just as I did. Why spend 10 hours gettings herbs in zones my level when I can come back at level 70, deal without threat radius, and accomplish the same task in 1-2 hours.
4) Beauty is in the eye of the beholder. If you want more joy, then use the script for x1
5) This depends on the person. Saying 50% of the game is a leveling process is probably a bit excessive. But of course - opinion. A majority of the game play exists in PvP and PvE progression.
6) The only things that will effect economies of games are the population of producers and consumers. As it is - all purchasing power rests on 70s. Having an extra 200-1000 level 10-60s running around wont significantly impact things. Plus, typically for every 1 producer there exists 1 consumer since that's the way professions are designed. As servers age, the population becomes more consumer heavy as players switch out professions to maximize benefits towards their goals (PvE/PvP/Wealth). If the population of producers does not fluctuate dynamically with the shift in consumers, supply deficits occur - resulting in regular commodities being super inflated.
Ie: There exist 20 skinners and 30 leatherworkers - (Lets assume that 10 players are doing both)
A shift occurs where the population does not increase, however 50% of those skinners decide to acquire a new profession (because originally they went for 2 gathering professions) for additional gains during their career.
There now exists 10 skinners and 30 leatherworkers.
Since the LW's are still consuming for drums and leg armor, the price of knothide etc will rise steeply (20 people all trying to buy the same thing).
Any source of new players stymies this from occurring as the life cycle of players continues.
7) While it is true that people will play pre-bc regardless of the experience rates - there will be inherent burn out from pre-bc players, or those wanting to explore their curiosity in this content. Being that they likely came from a x1 retail environment, the best way to curb the intimidation of leveling AGAIN is to accelerate the process. Whilst there is a sect of folks who romanticize leveling, it is fair to say that after 8-12 years for some people - its just a nuisance now. An obstacle we wish to overcome sooner rather than later.