I hope not to be "accused" of being a late weekend XP whore: I would like to report an issue with the indenting of nodes, which is actually shared by any system that allows for arbitrary levels. (It happened to me with Disqus too, a CDP I use to add comments to my tumblelog, also implementing a hierarchical commenting system.) To put it briefly: the layout screws up when levels go deep enough.
As far as my last PMD questions/requests are concerned, it has always turned out that there was a setting already doing what I wanted if turned on or off, but I'm reasonably confident that it's not the case with this one: I am aware of the Replies header depth and Replies text depth ones under User Settings: I have them set to the maximum possible value, which is what I want as far as content is concerned. I'm claiming, though, that as far as visual representation is concerned, indenting by a fixed amount of horizontal space beyond some given threshold is not sensible, and either a fixed limit should be imposed or a flexible one, in terms of another setting. (I believe that if it is a matter to be taken into account, it may be implemented through css by supplying different classes respectively before and after the threshold has been reached.)