I would like to call every ICE artist diving into Houdini to discuss porting the very practical (and not so granular) nodes Softimage provides to Houdini so we can make the transition even easier.
Many of these nodes I am sure will appeal the Houdini community, like the various statistic related tools, so it will need some help on the translation to Houdini.
One thing I've missed a lot is the “UV to Location” node that works on nurbs curves and surfaces which lets you feed in a u or v coordinate (or array of coordinates) and evaluate the curve (say, to get P, Normal, and Tangent) at that parametric location.
Also a mechanism for geometry traversal would be nice, like if I have a primitive handle I'd like to be able to get the prim's points and iterate over them, for example.
In VopSops it would also be nice if there were OpInput ports in the Globals in the same way that they have them in the AttribVop Globals, that would make any of the geometry query nodes (pcOpen, xyzDist, etc.) quicker to set up.
Of course also the statistics nodes (max/min/average in set) in SI would be nice to have out of the box (instead of having to build detail attributes beforehand - there's something to be said for having as much of the relevant data in the same place instead of scattered about), but I can understand maybe why they don't exist (or why if they did, they might impact performance adversely).