Adam Omelianchuk explains his problem with Calvinism in "My Distaste for Calvinism Made Public" at Evangel, and, I think, accurately describes the unease many of us feel about aspects of Calvinism.
....I think the main reason why so many protestant Christians have a problem with Calvinism more than issues related to Catholicism is that they see Calvinism as a plausible system. That means it is a reasonable one that could possibly be true (sorry, but some of those beliefs about Mary are just plain silly). I remember being introduced to the theology 11 years ago through the “limited atonement” piece of the puzzle, and I still remember the violent reaction I had to it. It made the strange view of Open Theism look attractive, but Calvinism’s plausibility created a long-time of wrestling that ultimately resulted in a (short lived) conversion to Calvinism.A commenter suggests that his distaste for Calvinism has been colored by his experience of Calvinists:
What eventually lead me away from Calvinism is what drives much of my distaste for Calvinism today and yesterday: God is made untrustworthy. This may be hard to understand, but the impetus behind Arminianism and other free will theology is not human pride’s assertion of autonomy but the concern for God’s good character. If Calvinism is true then God determines all of the evil in the world and in us, yet is somehow not responsible for it. While this presents an obvious philosophical difficulty that I am not sure can be resolved, I still found that God was very difficult to take at his word even when I was able to resolve it in my mind. For example, the texts that say God wants to see everyone repent and be saved simply could not be taken seriously. Yes, they spoke some sort of truth about some sort of divine desire for everyone to be saved, but it certainly wasn’t anything to bank your salvation on considering you knew better that God “damns people for his glory.” ....
God’s glory is not revealed in a distant egotistical God who must destroy a sizable part of humanity in a lake of fire in order to maximize his glory. He is revealed in a man from Galilee who takes away the sin of the world. He is not the kind of God who is content to rejoice over a small select group of “righteous” people, but, like a shepherd, leaves the flock to go after the one who is lost. God’ character is best understood through Jesus of Nazareth as one who does not snuff out cooling embers and bruise broken reeds, whose glory is in making all things new through self-sacrificial love. Those that reject this love are lost, but this mystery of iniquity is found in the soul of humanity, not God. .... [more]
...I have never encountered a Calvinist who really explained himself in a beautiful, winsome way. There always seems to be something… Napoleonic? puglistic? Grinch-like?… about the way that Calvinists explain and defend themselves. This is a reaction to a personality rather than to their theology, of course. Unless the two are related.And then some rather pugilistic Calvinists show up to reinforce that point.
Someone I read recently [I don't remember who] described himself as a "Christmas Calvinist," that is "Noel" [no "L" — no "limited atonement"]. That eases things quite a lot.
My Distaste for Calvinism Made Public » Evangel | A First Things Blog