xp is better than it was... and during dbl xp weekend i went from lvl 6 to 40 without super try hard mode... and my duo partner went 0-38 also... or maybe more and thats still while raiding as per normal
I think it largely depends on your class/synergy and knowledge of where to go at certain levels to maximise what you are doing/aiming for... if you want to skip rvr and purely XP, or if you want to balance it with rvr also... but also knowing when to re-upgrade your gear and what tactics are going to give you maximum return for the style you are embracing...
So newer players will lack this knowledge, and grizzled veterans will always be grizzled veterans and always hate to re-level again for the nth time... I have level'd close to 30 40's now on live / ror combined... its alot doing similar thing over and over so i can understand both sides of the coin and why people complain to be honest, and also why dev's also get a bit defensive because they have improved some things compared to what they were... and closed some xp loopholes.
I think the main issue is lack of knowledge/ managing(maintain) people's expectation levels of some classes, people start playing something and not as effective as they can be (gear(missing talismans/pots)/tactics/add ons or its build or just the class itself is really a late bloomer or very niche) and becomes a real slog and then half way through leveling they will get bored / find out they don't like it so have to re-roll the dice and try again until they find something they like... to me the game only starts at 40 and once you only have certain gear... that takes alot of effort for some whilst they know what they are getting into, but it is what it is.
If you compare some classes on leveling solo, there are some big gaps and some are a complete nightmare... but if you put them in right duo combination then its no problem what so ever. So new solo players will have it pretty rough, without a semi warning the difficulty rating of class/leveling as its old school mmo it gives no quarter
like some people complain about BW solo leveling because the self damage, the breaks needed to regen... the fast respawn rate of mobs in certain areas... but give it a pocket healer or solid tank and bob's your uncle...
Pure healers generally lack dps, just like pure tanks so to solo on something which time to kill is terrible is very boring/tedious... that is why DPS healers make good leveling characters and you see them join t4 sc's and get farmed hard because dps healer needs proper rr/gear/protection to function... where if they joined SC as lowbie Heal they can handle some pressure and contribute alot more and most instances can be the real mvp... its just one of those things of knowing your strengths and weakness of the path you take. Im not sure if a leveling guide exists here, or class specific leveling advice to make the tedious ranking go faster, but maybe it would be useful for new players... just a generic at XX level... this is your general options, this PQ is good to farm if Solo, or this if duo/greater ... I think that's better than just whining about a problem, that is less than before.
As for learning your character argument... if you pick up bad habits you likely keep bad habits until someone you listen too more knowledgeable or experienced than you sets you straight in a constructive manner (like i ask for advice from others who are more specialized at different roles/classes if im unsure), and pve leveling is totally different to pve lairs/dungeons and its also different to sc and also different to "roaming" or "large scale" they are all seperate genres, and its also different depending on group setup
General advice to leveling is too work in a duo or greater, to cover your characters own weakness and you will make leveling a better experience atleast.
Its like Mara / dps dok is so amazing to level compared to others... (heal doks suck in t1 compared to shaman/zealot even if you try hard in comparison to another try hard) just little things like this knowing when the power curve kicks in and things start to balance out for class (so expectations are kept in check)
Same with DPS WP its great to level, but you try grinding stuff with your little hammer and book alone =
If you want to level as a SNB tank... level with a aoe dmg dealer
or just for leveling go 2hander tank and level with a dps healer
if you are aoe dmg dealer level with a snb tank or pure healer