I see God as intersticial, existing not only in everything but also in all of the spaces between things, in the connections, infinitely loving and compassionate. Yet when people begin to describe God as wrathful and vengeful, thus destroying connections, that seems to me to be one way of describing evil. (Do I need to accept these as qualities of an integrated God?) I also think both good and bad thoughts come from our own minds and our experiences. But, when I hear that "still, small voice," from where and from whom does it come? Especially when it asked me last year, "why do you deny me?" an ironic and humorous question I'm still pondering.
I see “sin” as separation from self, others, and God. If we choose not to listen and respond to a loving and compassionate God, well, we have free will and can choose to do harmful things, but that doesn’t limit God. But could God ever be separated from the Godself? Jesus seemed to feel that disconnection briefly while on the cross, so perhaps yes, since he is our greatest example of a life of continual connection with God, even as Godself.
I tend to think that the “end of time” (or the "Advent") could refer to the absolute present (past, present, and future all one). “Final judgment” could mean that all will be incorporated in God, and thus we will know all of the harms/evil done in all times, as well as all of the love/goodness. To know infinite darkness as well as infinite light—unimaginable pain and grief as well as joy and rapture—could be horrible and terrible and wonderful and amazing. That’s why it’s important to act in the belief that we are all connected (whether or not we feel this), to love all—self, enemies, friends and family, those who are unknown—because all will be revealed when we abide in God.
So perhaps the questions of whether or not evil and Satan exist are moot, if we could live out this last principle, the way of peace.