Cornelius Van Til should be treated as all scholars should be treated - praise and use the good stuff he wrote and criticize the things he wrote where you think he went wrong. Any scholar's published writings are fair game for both sides.
One thing Van Til should be admired for is that he was one of the first scholars writing in English (as far as I know) to criticize Karl Barth in print at book-length (The New Modernism, 1946).
On the other hand, Van Til is now undergoing criticism for his approach to apologetics, as I noted in my OP with both Richard Muller's review article and John Fesko's new book.
Like every other writer, Van Til can and should be admired for his achievements - but, like every other scholar, he is not beyond criticism.