1: To do Algalon you need the key. To do hardmode Trial of Crusader (or w/e) you must've completed the normal mode. Not like the old days, but attunements nevertheless.
2: They sucked in Vanilla too. Ashkandi was better than Sulfuras, only Thunderfury was worth something due to it's debuff.
3: Onyxia! 40 man, no please
4: Plenty of those.
5: Would be nice, but rather massive
Now what I'd like:
1: Raids where fights challenge players seperately.
2: Raids where fights split the raid up in smaller group, each group must take care of their own group (cannot lead centrally due to random factors)
3: 10v10 arena with added PvE elements (mobs) so tanks are required as well.
4: New player models
5: Moar lore and dragons. Never enough dragons.