The Phoenix-Five is like the Highlander scenario: "There can be only one!" And Emma has pretty much embraced being bad. The murder of that dude, plus being the thought police to make sure all the students worship and adore her. It's like all of her already present negative personality traits have been multiplied.
Regarding Hope & the dragon: Hope's power is to copy the powers of any mutant she's near, right? So I guess the dragon is a mutant? Hell, maybe it'll become the newest member of the X-Men.
