1.Competency mapping( Broadly. Based on the time available to you you can work on all stages of competency mapping.Or else you can workout on a narrower scope by taking some of the sub divisions mentioned below:)
-Defining roles and creating Job Descriptions
-Identifying the developmental needs
-Training and Development need analysis and developing a training calendar
2.Study on employee engagement and the relevance of it.Support it with employee satifaction surveys..may be you can link it to attrition too.
3.A study on the performance management system in an organisation and providing suggestion for improvement.