First of all, the Sunwell was cleansed and sparked back to life. That has a big effect on them as a whole. All Blood Elves are, are just magically fel tainted High Elves. After completing the Sunwell both High Elves and Blood Elves are seen together. The High Elves obviously want access to their homelands again because of this restoration.
I think the Quel'Dorei and Sin'Dorei should get over each other's moral differences and focus on the fact that 90% of their race was destroyed and they should grow up and work together.
I think Blizzard should add cool effects such as all elves should get a buff when they enter their homelands (Quel'Thalas). The Sunwell affects their land so they should get a buff. 25% more mana and spell power.
Blizzard should spend an expansion on actually rebuilding Azeroth and then they should send us to Argus to help the Draenei's out to reclaim their sacred planet or something. However I would love to see updated lore on all the races as well as new models for them. Blizzard always says it takes too much time to implement all of this, well then turn it into an expanision. Have heavy phasing, every quest you complete with your race should actually change when you complete it. They should have quests that stick, when the Blood Elves reclaimed Ghostlands, nothing changed... Phasing should be worked in so that once you completed the right quests, they actually showed change..
Just my two cents.. What do you peeps think? By the way i'm not trying to jump to another expansion, just would love to see a more reliable source of lore updates.