The three individuals who have had the most effect on me through the years would undoubtedly be C.S. Lewis, Francis Schaeffer and Thomas Oden. Lewis definitively believed human beings have genuine free will, Oden was a Methodist and thus was in the Arminian camp. Francis Schaeffer was a Presbyterian, and presumably a Calvinist, though I have noted that in all his writings I never once detected any hint of the divine determinism common in the brand of Calvinism that has so much influence today.
I stumbled across this post from May of 2016 by Douglas Douma, a minister in the Reformed Presbyterian Church and author of he Presbyterian Philosopher – The Authorized Biography of Gordon H. Clark.
Douma finds evidence that Schaeffer was uncomfortable with the implications of 5-point Calvinism:
"Nowhere in Schaeffer’s writings does he give a positive appraisal of the Calvinist views of election, predestination, or divine determinism. In fact, it seems he avoided the topics entirely."
