Due to the contradictory and confusing nature of Calvinism, Calvinists often struggle to articulate their own arguments. So Arminians with whom they are in dialogue, are often found having to first unscramble their own logic puzzles, in order to provide an answer.
One such Calvinist logic puzzle is the following: “In Heaven, we will not be able to sin, and yet we will be free, which proves the doctrine of Compatibilism, in that God can irresistibly determine our actions, while yet we remain free in what we choose.”
As a response to what kind of free will that we will possess in Heaven, I personally think that we will have a full, free range of libertarian free will in Heaven, but that there is an added dynamic that is overlooked, because our sin nature is the only nature that we presently know. And so we perceive a future through that lens alone. But, the Bible indicates that we will receive a new nature. In our new nature, in our resurrection bodies, we may think differently, perceive differently, experience things differently and process knowledge differently, which together with the divine nature, may result in free creatures operating with complete freedom and yet also spotless innocence. A third of the angels fell, and their nature became irredeemably corrupt, whereas the opposite effect may have occurred with the other two thirds, and that being an incorruptible nature. So when you consider what kind of nature that we will someday have, that must be part of the equation when considering the kind of free will that we will possess.