Scripture does not support your either/or claim; nor is there any logical reason to demand such a sharp distinction.
Scripture does indeed tell us the God is sovereign. And Scripture also tells us that we are responsible for our actions: Jesus promises judgment, and calls for repentence -- neither of which make sense unless our own efforts matter to God.
One need not claim anything like equal roles in the matter of salvation; but it is contrary to Jesus' own words to claim we humans have no role in it.
Sure it does. And thank God it does because it makes life so much more joyful to know mercy is truly unmerited, and we are saved by grace and not debt.
Much more then, being now justified by his blood, we shall be saved from wrath through him. For if, when we were enemies, we were reconciled to God by the death of his Son, much more, being reconciled, we shall be saved by his life. " -- Romans 5:8-10"But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us.
Saved while we were still enemies, still sinners.
Read Ephesians 1. Our salvation is all part of God's grand purpose in creating in the first place.
"Therefore said I unto you, that no man can come unto me, except it were given unto him of my Father." -- John 6:65