You've already identified one major roadblock - getting your app noticed in a sea of similar apps. Thus you really must absolutely push any edge you have.

About the analytics you derive - who are you targeting it toward? Individuals? Power users? Consultant/freelancers? Small business owners who want to see what's taking up all of their employees' time? Large enterprises who can use this to increase employee utilization?

You might even think about marketing just the analytics, and "bundling" the task app. Good luck!