3. Monitor app crashes
Just make sure that the app is not crashing or the app is crashing, few times comparing to all app users. The high number of crashes can decrease your ranking position.
Users rating, and reviews are affecting so much on app optimization. App store rankings are depending on the review counts (It doesn't matter if your app is 3, 4 or 5 stars in user rating reviews). But it's important that it has so many reviews. And it's good for you to reply to those reviews.
5. Deep linking
It is also important how many websites or apps are linking to your app's deep link or to the store link of your app.
6. App size
Try to design a small-size app. Very huge sizes of apps are cause low ranking, or the users are not motivating to download it.
There are still hundreds of ASO tips, we can do for you. Feel free to contact us.