Thanks once again for interacting with us regarding the plugin.
Can you help me understand your request, I'm not sure I get it all right.
As I understand it, what you miss is the delta graph? That is a graph like the "Lines of code (delta)" in your example https://wiki.jenkins-ci.org/download/attachments/37322820/cloc_trend.png ?
That is because our current graph is hard to read, if you want to see if there is added 5Kbytes or 8 kBytes new memory use - right?
I think there is a good use-case for such deltas - we already also have logged this issue, about showing deltas on the build page and/or job page - see
Such deltas could, beside the graph you suggest, could follow the same concepts like the analytics plugins - see pictures.
We also hope to continue the work soon on the plugin and concept, and you might especially find the what we have called third and fourth development iteration interesting (https://wiki.jenkins-ci.org/display/JENKINS/Memory+Map+Plugin#MemoryMapPlugin-Thirdandfourthdevelopmentiteration).
Basically this is a drill down feature, so image to click on the graph dive down into the details on what actual code uses that memory and in which sections are it used. For example inspired by the Cobertura coverage plugin drill down feature, showing details like this: https://issues.jenkins-ci.org/secure/thumbnail/18656/_thumb_18656.png