I really love the section tools and paneling tools, these were/are really, really good and useful additions to rhino. Clipping plane currently as implemented is pretty much useful for me only for viewing and then suffers from all the caveats already mentioned.
I wish Mcneel would combine the two and really get sectioning working:
What needs to be looked at:
1.Sectioning for viewing iron out and get rid of all the caveats users reported
2.Sectioning for working geometry of off or on top of, needs serious attention and should be implemented with this new geometry/smart snap thing/layer you guys are working on.
3.Sectioning for layouts should auto generate into plan and detail views where it is updateable and without the current headaches that area has.
Then combine these into one command that really works robustly without all the caveats and bugs.