Here's an interesting quote from James Luther Adams from his essay "Arminius and the Structure of Society" in Man's Faith and Freedom: the Theological Influence of Jacobus Arminius.
"We should not forget, however, that in attempting this reformation Arminius remained in certain fundamental respects a Calvinist. He retained the conviction of the sovereignty of God, the sense of man's ultimate dependence upon God in Christ, the protest against the idolatry that gives to the creature the devotion that belongs to God alone, the strong moral passion, and the demand for social order."
He goes on to say:
"At the same time he was vividly sensitive to the power of God which manifests itself in compassion and tenderness, to the power that gives new liberty in the gospel. Arminius took seriously the promise, 'And I, if I be lifted up from the earth, will draw all men unto me.' We may say that affection, attraction, or love, rather than will was the fundamental pathos of his life-view. Through providence and love man has freedom to accept or reject the power unto salvation in Jesus Christ."
Arminius is sometimes portrayed as being a significant divergence from the Reformed tradition. Adams indicates, rather, that it was an in-house debate.