Wild, random theory: Is anyone else getting the impression that Zoom as the season's "Big Bad" is being set up as a false lead?
For starters, there is the thematic similarities between Zoom and Reverse Flash; except with the former lacking the personal connection Wells/Eobard had with Team Flash; making much of the storyline a retread of Season 1's. That even though Zoom is objectively more "powerful" than Reverse Flash, the story potential of the character is weaker in terms of drama and emotional payoff.
In addition, there's also how fast the show is blitzing through his storyline. We're barely a quarter way through the season and the show has already revealed his costume and are escalating towards a confrontation between Barry and him. In contrast, it was only at the mid-season finale that we got a proper face-off between Barry and Wells/Eobard.
As such, given the pacing, I think Zoom would make a better mid-season finale that then reveals and/or sets in motion the storyline and final "Big Bad" for the rest of the season.
Lastly, while on the topic of wild speculation, I think it's pretty much a given that [blackout]Wally[/blackout] will turn out to be [blackout]Iris' lost brother that her mother gave birth to after running away[/blackout].