The effect of all this is that while it's not hard to adjust, it could eventually involve rewriting a *lot* of transformations, and so it seems like the kind of thing to think about now before we commit to one approach.
Right, I don't disagree; I'm generally in favour of thinking things through. What I'm saying is that right now we haven't committed to a particular approach yet, largely because there doesn't appear to be a clear winner; it mostly just seems like different sets of trade-offs at this point. If you have a preference, and want to have a go at moving things in that direction, by all means go ahead. :)