Well, the Protestants don't have the complete Bible and they do not read what they do have in the light of the patristic tradition, so on that score your faith is not complete. Most strikingly, you don't believe in the words of the Holy Scripture that tell you that good works are necessary for salvation alongside faith, and that you are not saved by faith alone. So your faith, although it retains some Christian principles, is defective.
You state "[salvation] is by grace through faith and good works". A person, in your example, must have faith but must also perform good deeds and refrain from sin. You also say that good works can be canceled out by sin such as committing a "mortal sin" and not following the prescribed remedy which is repentance, confession and due penance. Also the "good works" you say are required include many acts, beliefs and states of mind which include complete obedience to the "Church" and her proclaimed dogmas and doctrines. In this way of thinking, sin can actually cancel out the grace of God and whatever faith we placed in it in addition to any good deeds we may have done before we died
Good summary.
my belief is that God, through his grace, has provided the payment for all our sins
The Redemption obtained by Jesus on the Cross is alone sufficient to all sins past present and future. That part is true.
All our own righteousnesses are as "filthy rags" compared to his own for us, so from that I realize that my good deeds, my good works as somehow being held at the same level or the same worth as what Christ has done for us is purely illogical. To hold that grace through faith is not enough if it doesn't also include our efforts negates the whole meaning of grace
No one says your good works are on the "same level" as the salvific work of Christ. Neither does the New Testament call anyone "filthy rags", -- basing your misanthropy on that is a result of uncritical and un-Christian Old Testament literalism, against which Jesus advised (Mt 5:21-22, for example). However, the scripture does say that your good works are necessary for your salvation (Matthew 25:31-46, Romans 2:6-10, many direct appeals to do good and avoid evil). So if you believe in Christ, do what He tells you: strive for perfection (Matthew 5:48), forgive others (Matthew 6:14), do works of kindness (Matthew 5-7) do penance (Acts 2:38). The smug concept that because Christ's grace is sufficient nothing is required of you is foreign to the gospel. "Why call you me, Lord, Lord; and do not the things which I say?" (Luke 6:46). "[I] rejoice in my sufferings for you, and fill up those things that are wanting of the sufferings of Christ, in my flesh, for his body, which is the church" (Col. 1:24).
Nothing will ever separate me from him
Nothing except you yourself through your own deeds or lack of them.
One says he has faith but he also tries his best to follow all the rules out of fear that he may lose Heaven. The other has faith and follows the rules out of gratitude and love because she knows she is held in his hands where he will never lose her, he will never cast her out
It is better to obey the gospel out of fear of losing one's salvation than not obey it at all. It is even better to obey the Gospel out of love for your Savior. One thing does not exclude the other. A Catholic Christian starts with the former and proceeds to the latter. The once-saved-always-saved are not even on that road; they, thanks to the Protestant charlatans that teach them convinced themselves to stay on the sidelines
How sad that in order to hold on to people, your religion uses fear of God to maintain its power. Just so sad. One thing the "once-saved-always-saved" - you so sneeringly deride - have all over you is the sweet assurance that being in the palm of our Father's hand brings. We KNOW we have eternal life - not wish, hope, plead or beg for - because we believe on the name of the only begotten Son of God (I John 5:13). His name means "God with us". Almighty God took on flesh and endured shame, beatings, insults and, finally, death upon a cross so that all our sins were paid in full. He paid the penalty our sin debt required.
So, like I said, you go right ahead and trust in your own good deeds and merits for your salvation. Let that be your motivation. I, on the other hand, will rest in the grace and mercy of my Savior Jesus Christ. I will lead a life that honors him, not because I believe I must do good deeds to be saved, but because of my gratitude for his love and the grace he lavished upon me and all those who trust in Christ alone for salvation. We have a new nature, the indwelling of the Holy Spirit that creates within us the desire to do the works of God. Because we love him is why we obey his commandments. You totally miss the whole point and it is your lack of faith that is defective, not mine.