We recognize that MoP is probably not the most alt-friendly of all the expansions and since WoW has been running for so long with its persistent world where characters usually don’t get deleted very often, it’s normal to expect a higher average number of alts per player as time goes on.
Our development team is very aware of this and they are trying to find more solutions for alts in MoP.
I have no solutions but want to give my feedback on alts in MOP.
A good thing is that it isn't necessary to complete all areas before moving to a new one. Therefore after the initial few quests in Jade Forest I can vary the quests I am doing to some degree.
Also, the availability of the battlenet account bound items that are found as 'treasures'. These will be most useful to give a head start at level 85 and I find it a fun thing to do.
Flying. Now I'm really in 2 minds here. Malindra is 3 bars from 90. All I have been thinking about since she turned 89 is please let me fly! but it's a double edged sword. For me the motivation of being able to fly is what keeps me plugging away. If I could fly now I might stop ordinary questing etc. So I really can't decide on that one.
In fact I would rather see the Northrend levelling experience tinkered with. As it stands, quests aren't open in the interesting bits soon enough, then we're off to Cata areas.
Obviously this is one view. I have no idea how the way I play tallies with my fellow players. A clue; for the two I have at 90, I did find myself thinking the other day s*d Golden Lotus rep, levelling up more of my pets is where I want to be. :)
To sum up, I don't think there is a huge amount needs doing for alt levelling in MOP, not for those of us whose goal, so to speak, is the journey itself.
For those who want quicker end game play on alts, I can't comment, it's not my experience.
Although Tiller/Angler quests opening at 89 would help alleviate the 89/90 pain & the mass of stuff suddenly available at 90.