In a team of developers, testers, BAs, etc. it can be difficult to plan a sprint and have enough work for everyone in the specified time box until you have a team comprised of the ideal 'T' resource.

As a Scrum Master, I would like the ability to specify a story's primary effort as 'Testing,' 'Development,' 'Analysis,' 'Operations,' etc. so that in the Detail Planning screen I can see a graph to easily let me know where we're heavy to do a better job balancing out the sprint.