Cookiecutter Roleplays
Nearly every roleplay posted on these boards are cookiecutter roleplays, or very common roleplay types that are pretty much clones of each other. Examples of cookiecutter roleplays include prophecies, wars, labs, and especially academies. Academies are SO unoriginal, overdone, and even kinda spammy. Think about this: every academy is just this form:
You have been invited to (insert something) Academy!
This academy is for (hybrids/special power dragons/erase if neither) dragonets!
The plot is (school being attacked/it was a trick/group of special students must save the world/chill).
Have fun, and I'm totally not being lazy!
See? All academies are just copied homework. Even worse, cookiecutter roleplays generally resemble events in the canon series. Academy roleplays resemble Jade Mountain Academy, most war roleplays resemble the War of SandWing Sucession, and lab roleplays resemble the NightWing labs. For Clearsight's sake, everyone on this fandom already knows those stories! That's why we're all here! Not only cookiecutter roleplays are copy-pasted from each other, they're copy-pasted from Tui! Can't anyone here be at least a little bit original?
Host Powerplaying
Regular powerplayers control the actions of other characters, but powerplaying hosts control EVERYTHING. Host powerplaying is a huge issue that has strangely never been addressed. Up until now.
"She blasted fire at him" is not powerplaying, but "She pinned him down" is.
Will the heroes prevail, or will they fail and allow the world to fall into chaos? is not host powerplaying, but Eventually Hero 3 will decide to betray the others and join the dark side because they know the heroes can't win and so the heroes lose is.
In roleplays with powerplaying hosts, all of the participants are the host's puppets. The participants have no freedom at all while the host forces them to type exact replies. If the host wanted the plot to be exactly as they want it to be, they should've wrote a fanfiction instead.
Roleplays with this kind of pain-in-the-tail host are no fun at all. If hosts want as many people as possible to join their roleplay, they should create one that everyone can enjoy. Good roleplays are open-ended and grant participants freedom to shape the plot.
The worst subspecies of powerplaying hosts control not only the plot, but also control the attributes of the characters themselves.
This is how a normal host would write this roleplay description: A power-hungry princess of the SeaWings challenged the queen and won, and now she's using her new title to take over Pyrrhia. Here's how a severe powerplaying host would write it: The power-hungry Princess Vortex of the SeaWings challenged Queen Seastar and won, and now she's using her new title to take over Pyrrhia.
See the difference? In the second example, you can't even choose the name of the newly-crowned queen. As for preset names for already-dead characters, Queen Seastar in this case, the name Seastar is restricted because it's already taken by the host. I've even seen one instance of hosts presetting entire OCs, name, gender, sexuality, personality, and all! (Note that canon charcater roleplays are not host powerplay because canon characters are supposed to have specific attributes.)
I would go as far to say that host powerplaying, especially OC-presetting powerplaying, is ban-worthy.
Conclusion
Nobody likes spam or powerplaying, including from roleplay hosts. Creating an original roleplay with a unique plot will help it stand out from the low-effort cookiecutter roleplays littering the board. Give the participants freedom to help shape the plot and contribute to the story collaboratively. And for the sake of Clearsight, let the participants choose their OCs' names and attributes at the very least! (Unless you're restricting special powers of course, twenty animi in a single roleplay gets very chaotic very quickly.)