@Mrmildock  
Indeed and that seems to be the direction these movies are heading. Gloriosa will probably face the same fate, unless she turns out to be a supporting character. Friendship Games just had too much focus on Sci-Twi and Sunset whereas Rainbow Rocks managed to put mostly an equal focus on all of the characters.  
The Dazzlings didn’t get much promotional material but RR was centered around them while with The Shadowbolts they got lots of promotional material but in their movie they were treated like nothing more than glorified background characters. Despite, The Dazzlings popularity I believe The Shadowbolts are more likely to come back since they’re redeemed and they’re not dangerous magical creatures.

@BlazingDazzlingDusk  
What hasbro needs to do, is stop making every new character a one off character. Heck, I’m upset that the Shadowbolts didn’t get any respect at all. You could tell what they’re like just by looking at them, but Hasbro thinks that sympathizing for one character throughout the whole film is a good idea. They don’t bother developing the characters around her (aside from Cinch). I also kinda hate how people keep comparing unfairly to the Dazzlings and act like complete jerks about it. As much as I want my three favorite sirens back, I want the Shadowbolts to come back and get the respect that they rightfully deserve.

All eight must come back in an eight hour movie with each getting their own hour of awesomeness. Then the credits can be a tribute to all their songs with Sweeten Sour making sporadic appearances throughout.

Personally, the only one I even remember as an individual is Sugarcoat.

Sadly as much as I love my Dazzlings, I was upset the Shadowbolts didn’t get the respect they deserved. All five really need a comeback. I really want to see them again.