Canonical no more?

In discussion of philosophical underdogs, Karl Schafer (comment # 49) and Dennis des Chene (comment #60), quite rightly raise the issue of scarcity in the philosophical canon (and opportunity costs involved in reviving the fortunes of previously underrated). In particular, when teaching there is only limited room for innovation in the syllabus. For example, thanks to Andrew Janiak's clever edition, which has made DeGrav easily available, Isaac Newton is clearly making a comeback in Early Modern curriculum. So, what went? I tend to drop Locke (and I use Galileo to teach primary/secondary quality distinction). I also tend to devote a lot of time to Spinoza (often teaching the whole Ethics, which undergrads adore), and that has meant less Leibniz or Berkeley. When I introduce Bacon's New Atlantis or Galileo's Starry Messenger, I sometimes drop Pascal's Wager or Swift's Gulliver's Travels. So, here's my question: which canonical authors have only tenuous hold on their status (assuming that Plato, Aristotle, Descartes, Hume, and Kant are risk-free assets)? In order to get discussion going here are some suggestions of philosophers whose Canonical status may be tenuous:

• Berkeley. I adore him but scholarship seems to be dwindling in numbers. He does not seem to have any serious modern interlocuters
• Locke. Still very significant in political theory, but scholarly numbers in M&E seem small, and outside discussions of essence/natural kinds and personal identity he is less frequently interlocutor for philosophers.
• Augustine. My sense is that the Wittgenstein inspired boom is subsiding, but maybe folk in Ancient will correct me.
• Wittgenstein. Certainly still very much studied. But the low-hanging fruit and even many of the deep insights have been assimilated; it seems that interest in Wittgenstein is becoming sectarian (with associated cult-infights). But maybe this is just my prejudice.
• Quine. Word and Object is aging very badly. I suspect in a decade or two, Two Dogma's will be mystifying to students, while Epistemology Naturalized will seem common sense. Of course, scholars will adore Truth by Convention forever.