I haven't seen your other species, so this is just general things I've noticed. + Some things for non-closed species as well!
- Semi-closed species: Either easy to get MYOs (less than a week of dailies, for example) or FTO gets a free MYO
- Don't overcomplicate the species trait-wise. Some examples of what I mean:
- If someone is getting a design approved, they should only need to list a few traits. It's easier for people to design if they only have to pick from 3 or 4 categories of traits than 5 to 10. This helps keep people from being overwhelmed with just the base traits.
Of course you can have extra traits that are optional, just add-ons. This balance allows for people to make simple and easy to understand designs, but the option is there for complex ones with lots of traits. - Color traits. Please don't limit colors. While some species do well with this by having good lore reasons, it's more freeform for people to not have to worry that a trait is too dark/light. (Exceptions ofc! I've sure you have seen reasonable color limits on species before c: )
- Try to avoid having traits that can overlap if too close to each other. For example; don't have bear ears and tiger ears, a mistake I've made before personally aha... Depending on the artist's style, those traits may look the same in their style.
- Maybe be open traited for "base" traits? Like any ear, tail, and horns (just listing common trait categories) and only "add-on" like traits require something more? (Like wings, flames, or twin tails)
- If someone is getting a design approved, they should only need to list a few traits. It's easier for people to design if they only have to pick from 3 or 4 categories of traits than 5 to 10. This helps keep people from being overwhelmed with just the base traits.
- Have the information of the species in an easy to find place on TH. People don't want to have to join a discord to see the species. If you set up a site, have the information in a place where people don't have to sign-up to see it. When hosting images in forums, don't use Discord as they time out and you'll have to replace them.
- Have lore. Even if it's a little, have some.
- Be invested in your own species. Have a mascot ready for launch, have OCs for yourself. Even if the species doesn't pick up, make your own fun! People are more willing to join when they can tell the owner/staff enjoys the species and isn't just looking for a payday.
Other questions to think about, you don't have to answer. This is more of questions for yourself.
- Why do you want a popular species?
- What is it about species that you like?
Anyways, hope that helps! Others are free to add to this!