Thanks @Bennylin for sharing the useful feedback. I have provided the response below each of the comment.

There’s so much blank space in this step that beg the question: what can be added in this step?

Reason to keep space on this screen is to keep creator’s attention on story title field and some space to accommodate error messages. Also, mobile device keyboard reduces some space further. We will re-look at publish screen again based on other improvements on publish page.

User (a.k.a. me) could forgot the title of the article, or at least the exact wording of the title. It happened to me yesterday, and I have no way to know the (exact) title of the page I’m at (other than to start over, but that would be Very annoying). So, please display the title of the article at this step. Displaying the Wikidata description underneath would be a plus (I’m not sure if that’s my gadget or default feature in id.wp). PS: Hitting the back button is Not intuitive in this scenario. At the very least, autofill with the article name, like in step 1 (choosing images), although I realize this would conflict with #3 below (choosing unique title).

We will explore design solutions to show article title on the publish page and see how it fits with other items available on the publish page. We have created following task(T320791) to address the device back button scenario.

There’s no way to know which Wikistories title is already taken (when there’s ton of Wikistories, like id:Kucing, and it could frustrate users. I suggest to display all Wikistories titles of that article below the textbox. To avoid over-information, the list could be not shown by default, and only shown when the user click “Click here to see all the Wikistories that have been made” button or something.

Thanks for the suggestion, we need to consider over-information scenario a bit more in detail as displaying stories attached to an article might not be sufficient given duplicate story titles can exist in other stories too.

And since this is a beta feature, you should never assume the user know that Wikistories title have to be unique, since there’s no indication anywhere in this step. Therefore please tell the user so when they are at this step, and not after they gave a title that’s already taken. (Plus list all the taken names, otherwise, they might fail to input a non-yet-taken names after several tries and get frustrated). When a name is taken, auto suggest other names. Either use numeral, or other suggestions.

We will consider adding hint about the story title.

A spellchecker would be a bonus, since many times I found users had typos in the title. And there’s no easy way to change the title/redirect the page. (Please make this easier! At least put the link to Special:MovePage/Story:... in the three dot menu). I had to make id:wikipedia:Wikistories/Permintaan bantuan for this.

Could you please share a couple of examples of stories with typos?