PC, are you saying that the Spirit-filled Christian's heart is still deceitful and desperately wicked? Is that the T in TULIP, and do Calvinists believe there is no difference when we are born again of the Spirit?
The time for comprehensive confession of all known sin is right after receiving Christ as Saviour. We know that faith in Christ saves us, and so the confession of all known sin is the essential first step in the sanctification process. This is not that we start to try and reform ourselves - something we cannot do without ending up being self-righteous. But discussing the sins with God fulfills 1 John 1:9, and as soon as we confess them, God forgives, cleanses and forgets that we ever sinned in those areas. This can be a real cleansing process and the lightness, joy and relief is so real afterward. It is not enough to say, "God forgive me all my sins". We have to name them before God one by one, and if we need to make restitution to someone we have wronged, we do our best to do it.
For example, when I left one city, I had photos that I had put into the shop for developing which I never collected. Two years later, the Holy Spirit reminded me of them, and I contacted the shop, paid for the photos and had them posted to me.
If we have a known sin that we are refusing to discuss with God, then it may be that we are not fully converted to Christ. This is because we cannot hold on to sin and have Christ as well. We may be saved as of by fire, but there will be a blockage in the Spirit for us until we get it right with God.
It is not so much that the converted heart is deceitful and wicked, but the devil is very much so, and he can give prompts to cause us to believe that the particular sin is not so serious and we can take our time getting it right; or that when we need to go and get something right with someone we have wronged, the devil may tempt us to procrastinate and intensify the sense of embarassment and fear - which is basically pride preventing us to humbling going to someone and telling that we were wrong in what we did to them.
Having said that, it may not be possible to go to a person when we have lost contact with them, and the Holy Spirit understands this. But we can pray that the Holy Spirit organise a way to contact if He thinks it is critically important that we put it right.
But certainly, if we have stolen from or cheated someone, we should make every effort to pay them back what we have stolen from them.
The main deception from the devil is to make light of the need to confess every known sin and to request the Holy Spirit to hook out hidden and forgotten sins, in the same way that my ginger ninja cat (the one on the left of the post) can hook cockroaches out of places I would never know were there.
The other deception is once we discover sins that need to be confessed, we try to get the victory over them in our own strength instead of doing nothing about them in the flesh and trusting the Holy Spirit to work in us to enable us to forsake them.