Suggestions on refactoring a poorly written ASP.Net MVC web application

I have recently "inherited" a project written in ASP.Net MVC which has quite a few issues and I'm looking for suggestions on how to go about refactoring the code.

The technical issues found so far are:

1. All the business logic is written into stored procedures (1000+ SP's).


2. No unit tests.


3. View Models are poorly used.


4. Views are directly dependent upon the database structures.


5. JQuery is poorly used - No js frameworks (knockoutjs/angularjs/etc..)


6. Quality is poor.


7. Performance is poor.


8. Non-Responsive Design (though it's meant to work on all devices)


9. No IOC

The other issues:

• The application is live and multiple users are using it.


• New features are being added to it as we speak and approx 40% of features still need to be implemented.


• The time to refactor is quite limited as the push is on feature release. Rewriting is not an option.


• Development team would need to be convinced about the shortcomings.

I would like to start small and make incremental improvements, any suggestions will be most welcome.