Quick rundown on the benefits of random walk SSS vs the current implementation?
TBH I think there are more pressing things that need work over SSS improvements (tone mapping!)
You're absolutely right, there're more important things to work on right now. Random Walk SSS should be treated as a suggestion for the future versions.
The first and foremost advance of RWSSS over Gaussian is its accuracy, especially on models with thin parts.
I think, implementation of RWSSS is just a matter of time.