so it is not only the code that can use some diet ;)

really, jetpack is a no go as long as it tries to have more lines of code then wordpress itself. The security and side affect risks are just unbearable to any non trivial site in which stability of the code is a must and plugin upgrade need an approval from 10 different people.and a rigorous QA.

(going to the gym to work on my own diet ;) )