One can make the following chakira (I think this is the second time I have posted a "machshavadik" chakira; no reason not to use the tools of lomdus in the area of machshava): does a person naturally have bechira chofshis (free will) unless some extreme circumstance causes it to be taken away, or is a person naturally either statically good or bad unless granted the gift of bechira chofshis (free will) to change by Hashem?
The question is asked how could Hashem have "hardened Pharoah's heart" - it's not a fair test? If one assumes the second possibility, the question is far less explosive (if it is a question at all). Pharaoh was naturally a rasha; he was given the gift of bechira to see if he would seize the opportunity to rectify his life. When he failed to take advantage of the gift he was given, it was only fair for that gift to be removed.
The interestingFOIL is the two sides of the no bechira coin in Shmos: Moshe, no bechira and therefore tov, and Pharoah, loses his bechira and is ra.