You are on the right track.
I would note that salvation is also so simple that even a child can understand and be saved. If you trust that the work of Christ is enough for your salvation (that Jesus died for your sins, and rose from the dead), then you can be secure in your salvation. Where does the Bible teach that? Is that what Jesus preached? Did Paul teach that?
Paul did say if we confess with our mouth and believe in the heart that Jesus rose from the dead then we shall be saved but he also said that those who are Christ's have crucified the flesh with the passions and desires and that the children of God walk according to the Spirit putting to death the deeds of the body.
Repentance means 'a turning of your mind' not necessarily a 'turning of your ways'. It doesn't? So a murderer can change his mind about his murdering but still keep on murdering people? An pornography addict can still persist in viewing porn once a week? A drunkard can still keep getting smashed? Is that what Nineveh or the Prodigal Son did when they repented? The fruit mentioned in John's letters should be present in a Spirit filled believer, but don't put your trust in your work or your repentance. It should be but it is not a requirement right? The why did Paul preach repentance PROVEN by deeds? Trust Christ alone, and good works will naturally follow. When do the good works follow is repentance is not inclusive of a change of behaviour? A year? Two years?
A changed life is a sign of salvation, but is not the way to salvation. A changed life resultant of a purified heart IS salvation. The way in which modern theology has disconnected manifest heart purity which necessitates outward righteousness from salvation is a most awful thing and is the very reason that sin cannot be effectively preached against.
I really hope some people can see the fallacies inherent in this "trust in Jesus alone" gospel which is being preached almost universally today. Trusting in Jesus in the Bible is presented in the context of YIELDING WHOLEHEARTEDLY TO GOD. There is no such things as being in rebellion to God and trusting in Jesus. Repentance is the change of mind resultant of the rebellious spirit being broken and the result is an obedient saint. Obedient to what? To the righteousness of God. We are slaves to whom we obey. That is what the Bible so plainly states.
Paul stated that we are set free from sin through obedience from the heart.
Rom 6:17 But God be thanked, that ye were the servants of sin, but ye have obeyed from the heart that form of doctrine which was delivered you.
Rom 6:18 Being then made free from sin, ye became the servants of righteousness.
If that is the case how is it possible for someone to claim that repentance does not necessarily involve a change in lifestyle? If repentance is not connected to a radical change in lifestyle then it simply is not repentance.
No adulterer repents and approaches their wife whilst still engaged in an illicit relationship. No sinner approaches God seeking mercy still in rebellion. Don't be deceived.
Isa 55:7 Let the wicked forsake his way, and the unrighteous man his thoughts: and let him return unto the LORD, and he will have mercy upon him; and to our God, for he will abundantly pardon.
The Bible is a harmonious whole and not a book of proof texts to be snipped and isolated out of context. Believing is inclusive of abiding. Abraham believed God and due to this he was a DOER of the word. Noah believed God and due to this he was a DOER of the word. There is no such thing as a believer who is not a doer, people who are not doers and claim they believe are liars.
Mat 7:21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
Mat 7:22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?
Mat 7:23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.
Mat 7:24 Therefore whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock:
Mat 7:25 And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock.
Mat 7:26 And every one that heareth these sayings of mine, and doeth them not, shall be likened unto a foolish man, which built his house upon the sand:
Mat 7:27 And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell: and great was the fall of it.
Jesus said DO, not simply TRUST. Real trust involves doing.