My view is that the atonement was sufficient for and provided for all but efficient for the elect only. Only in the case of the elect is the gift of faith imparted through regeneration by the Holy Spirit. My view of irresistable grace is aligned with Calvinism.
Now, I see the logic of making the extent of the provision equal to the extent of it's application, I just find key texts that keep me from connecting the dots. Both the work of Christ on the Cross and the work of the Spirit in regeneration are required in the redemption of the elect.
I think that we are on the same page somewhat. In the end analysis, not all sin is atoned for since hell will be populated with those who have no covering for their sin. If the atonement is limitless, then all are saved.