Agreed. Without Grace, there is no salvation. So as you say, Luther’s “sola fide” is not correct, but “sola gratia” is. Actually there is a passage in the much maligned Council of Trent that makes that clear.
Curiously enough, Milton—who was anti-Catholic—gets it right in Paradise Lost. We have free will; but that free will is enabled by grace. Without the saving Sacrifice of Christ, we would have no truly free will. Freedom of choice was God’s gift to Adam and Eve; it was subsequently lost in the Fall, but given back to us again through the Sacrifice of the Cross.
So, Calvin was wrong on that point. We are not saved in spite of ourselves, like it or not; we are saved because we freely choose to do God’s will, enabled by His Grace and by what Milton calls God’s Umpire Conscience, which as St. Paul says, is “written in the heart” of all men.
Because God is a loving God, He wishes to be freely served, not forced to serve. Again quoting from Paradise Lost, in the words of the Archangel Gabriel, “freely we serve, / Because we freely love, as in our will, / To love or not.” But that freedom had to be restored to us by Christ’s Sacrifice on the Cross.
Grace is The Gift, our acceptance (or not) is our free choice. That is the first WORK we must do - to accept His Gift. It is often not the last work we must do.