"One of the great challenges of learning philosophy" is actually separating the chaff ( something like 99% of what philosophers talk about) from the wheat.

Let's take your examples. Dualism vs monism can be boiled down to something like "can p-zombies exist?", which can eventually be answered by AI research and cognitive sciences. The rest is chaff. With free will, the situation is even worse. You write "no more precise statement can be made if we want to capture the actual breadth of thought", whereas plenty of more precise statements can be made, and are made, by outside researchers, like Scott Aaronson (see his paper The Ghost in the Quantum Turing Machine and the relevant discussion on his blog: http://www.scottaaronson.com/blog/?p=1951).

Incidentally, the two examples you mention are basically equivalent, as solving one clears up the other.