Tomes for 1 are a balancing Nightmare for developers.
AAs can be just as hard to balance for I would imagine. I do not dev but I don't see much of a techincal difference between a Tome vs an AA. You could have 1 "AA" that has 550 ranks that gives you 20% of overall power and call it the "Power Enhancement" AA. Devs can change AAs and Tomes to do what they want (obviously there are restrictions and I do not know if AAs have more/less/same as a Tome but it seems they are equivalent with the exception that some AAs like class AAs have timers).
Tomes also create a wall between new players and old players . That wall also takes months if not years to get over and hurts both new and old players alike leaving the group/raid Tiers Empty.
Walls kind of exist by the nature of the platform. You get exp to fill things (these "things" would be exp-able gear, tomes, AAs, possibly charms depending on how you look at it). Guilds/groups/content will usually have requirements, such requirements = walls.
To that, most of the time these "walls" are set by guilds or groups for other players they don't know mainly for the reason of being more "efficient" at exp'ing or raiding and breaking those other "walls".
Edit: I believe this is the crux of the CoP issue addressed in the OP.
I am all for making these requirements easier to attain for fresh players. I just don't see the current setup (of having Tomes) as an issue in that respect (other than say the rate of EXP for 100AA 65 and below which has/is being addressed via the recent new area bonus change and stuff).
There are two ways to fix the issue of the "wall" for new players because the longer an MMO exists the larger the wall since new content gets added (aka by design). (I can't think of a third way.)
1) You make new players go through the old content faster.
2) You leap-frog old content with "new" content designed to catch new players up.
Proposal #1 in the OP does what I listed above as #1.
Proposal #2 in the OP does what I listed above as #2.
3) Leave the walls and make new players suffer (not an option).
There are only a few players screaming fowl about a change that would keep more players then it would lose.
Removing all Tomes and by extension non-consumable AAs in general to start "fresh" just removes content that can be done and I don't get how that helps anyone.
No change is liked by everyone, someone is usually unhappy.
TL;DR - Tomes = non-consumable AAs. MMOs create walls by design. Players group themselves inside these walls and force new players to jump over those walls to hang with them. New players are cool dudes.
I don't mean to be aggressive if this post comes off as such. Apologies in advance if that is the case.