Attached is the current layout. I have been clicking the "Create" (repository) almost every single time I want to create a new issue.
As a user this means I am not comfortable with the current UI placement.
Placing the + Create Issue button right under the header Issues would be an immediate solution. I really doubt any user would want move their mouse cursor all the way to the right end of the page. Human eyes catch the center. The current button for creating issue is not visible to users either. That's why I and possibly other humans click on the Create button up there.
The reason why Github's button is fine even though it is already on the right end page is that the button is more noticeable, the page is center (eyes can easily spot that green button) and create new repo button is not right above "Issues".