Two substantive comments, and some editorial ones.
You write that you are thinking of different schemes for generating paths and ids. I suggest one of the things you consider is whether your scheme will work if someone cuts the ZWikiZC and pastes it somewhere else in the tree.
Yes, I realized a that my current design storing a WikiName lookup dictionary leads a need to update the dictionary from other object as the are move or deleted, maybe also when their added.
I'm not sufficiently versed in the different methods you discussed to understand their implications--they seem to involve yet more undocumented interfaces in Zope.
Not, really. They are discussed in the Zope 2.2 Wiki on zope.org. They are very hard to find thou.
It's hazardous to claim a performance advantage without benchmarks.
Yes, it should be scalability advantages. //Johan