The Windows Phone Developer Communications email in December had a focus on design. The main resources it called out were this list of resources and this article but it also included the below graphic, which highlights an issue I've talked, but not written, about before.
Unfortunately, there are people who see the above statistics as a shortcut to improved ratings. Good/high ratings are a side effect of a high quality, useful app that provides value to the person using it. Simply adding features doesn't automatically equate to an app that will get or deserve higher ratings.
Let's look at each in turn.
Wide live tiles
If an app shows data that is remotely updated and the person will that app installed on their phone will benefit from being able to easily see that content when it is updated, without having to open the app, then having that feature could be very useful. Useful apps get high ratings.
Simply adding a wide tile to an app that will never have new content to show to the user is a waste and provides no use. Adding it will not provide benefit to the user. (Which is why Microsoft recommend only adding a wide tile if it would be updated with changing information.) Doing something that has no value to the user won't improve ratings.
In a large app with many areas to it, being able to create deep links to that functionality can save people time, effort and the need to avoid repetitive navigation to get to what they want is a good thing. Doing good things for users is more likely to encourage them to leave a higher rating.
Regularly releasing updates can be a good thing if it's to release bug fixes and add new features that the people using the app are asking for and will benefit from. Making the app more stable and capable of doing more will encourage a higher rating. It is also likely to appeal to more people.
However, regularly releasing updates that don't fix bugs, enhance existing features or add valuable new features is a waste of effort. In fact it will probably lead to worse reviews as you add more, unwanted features to a buggy app.
Don't just add features for no reason. Focus on creating a high quality, reliable app that provides real value to the people using it and the ratings and reviews will come.