Wings of Liberty Plot Analysis: Prophecy missions

In this series of reviews I will be examining the plot of the various groups of missions in Starcraft 2: Wings of Liberty to highlight retcons, poor plots, and illogical decisions. Where relevant I will compare SC2 to SC1.

My main issues with the plot of the Prophecy mission are:
1) Why are the hybrids able to control the Protoss in one mission but unable to control them in any other?
2) That the Overmind was retconned into a slave who didn't want to attack the Protoss, even though in SC1 it willing attacked them and wanted to assimilate them so the Swarm would become perfect.
3) That Blizzard would retcon so much of SC1 just to create a reason why you can't kill Kerrigan because they want her to be the protagonist in the next game.

For more information about the problems with the plot of Wings of Liberty I recommend these threads:
http://sclegacy.com/site/editorials/7-reviews/1134-scl-reviews-wings-of-liberty
http://sclegacy.com/editorials/6-speculation/906-starcraft-retcons-analysis