1) The first mission is probably one of the best in my opinion. Not only does it create a sense of continuity among the campaigns (the setting is during the end of the night elf campaign, so it feels connected, like its all part of the same series), but it is fun to watch the AI fight another AI without the player needing to interfere. It is one of the most unique missions in flower fairy's campaigns.
2) Mission 2 was a good introduction RTS mission.
3) In the Nerubian mission, there was one lever that was incredibly hard to see. Also, the end boss fight is quite hard on insane.
4) The troll mission is probably one of the hardest. This is because you get the weakest solo hero (Kel'Thuzard) against masses of troll bases. The Gargoyle quest I think is not useful, since there is no unit in the troll army it can kill easily. If the gargoyle was introduced in the first mission against the humans, I think it would make more sense, since the air ships have fortified armour, so the normal melee attack of gargoyles is the best weapon against them.
Also, the end boss is extremely hard to kill unless you have 100 food of necromancers/meat wagons. Any other unit is useless, since you need range units + mass skeleton summons to win that fight.
5) The ship mission is interesting. I liked the design of it, allowing you to explore the map before your enemies become your enemies. Water terrain always makes maps look so beautiful, so I enjoyed this one a lot.
6) I enjoyed in the 6th mission how Noth had some dialogue about the zombies. It foreshadowed the plague mission very well.
7) The plague mission is probably my favourite of all the missions in this campaign. Using the zombies to flood/smash the other 4 human bases was extremely fun. A very unique mission design.
8) The final mission against the humans was good, but the guard towers protecting the city in the north had far too much HP. It took forever to kill them. Also, it would be nice to have a warning that the 2nd part of the mission was a defence mission. If I knew this, I would have mined more gold before completing the first part.
9) I liked have the faceless ones as enemies. It was a good choice of enemy for the undead. Also I liked how it showed their heroes early in the campaign (they were just watching us), and then at the end of the campaign we understand their true purpose.
10) The final RTS mission of the undead campaign was great! The only thing I comment on is I wish the ally AI would send more men to attack instead of 4-5 ghouls. Also, they normally ended up attacking the obelisks instead of the undead bases, since the obelisks were closer.
The ending had a good plot twist. I enjoyed the character development of Arthas in this, as he slowly became evil. At the start he even cared about rescuing the captured undead in mission 1 (side quest). At the end, he becomes an evil creature. Was really good! I also want to mention 2 things.
A) I enjoyed the dialogue between the evil human hero and his daughter. It provided really good character development for him, and I hope we see him again in the future.
B) I am concerned about the Dalaran forces helping the humans in the last attack wave while you defend Kel'Thuzad. Because now, He Xiaoshu (blood elves/dalaran) has relationship with the humans, as well as the orcs (from the 2nd campaign) and the night elves (because of Maiev). If all the "good" races are all allied, it makes it harder to develop the story with realistic conflicts, since the good characters all team together to fight "evil".
Anyway, really enjoyed this campaign, but I missed the strong ally AI from the night elf campaign/blood elf campaign. I really hope in the 4th campaign, Flower Fairy has more great AI allies
.