Paul speaks of certain sins as incurring God's wrath:
For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who by their unrighteousness suppress the truth.
And since they did not see fit to acknowledge God, God gave them up to a debased mind to do what ought not to be done. They were filled with all manner of unrighteousness, evil, covetousness, malice. They are full of envy, murder, strife, deceit, maliciousness. They are gossips, slanderers, haters of God, insolent, haughty, boastful, inventors of evil, disobedient to parents, foolish, faithless, heartless, ruthless. Though they know God's righteous decree that those who practice such things deserve to die, they not only do them but give approval to those who practice them.
—Romans 1:18,28–32 (ESV)
According to John Piper, "In Romans 1:18–32 Paul makes his case that all pagan Gentiles are sinners and in need of the salvation God has provided in Christ." We see a most bleak picture of the depths that humanity will descend and might assume that these sins are "worse" than others. Then Paul hits us with a rhetorical left hook:
Therefore you have no excuse, O man, every one of you who judges. For in passing judgment on another you condemn yourself, because you, the judge, practice the very same things.—Romans 2:1 (ESV)
So the first thing to learn about God and his response to hypocrisy is that God is just, and his just judgment is coming not only on the so-called pagan people who live in sin, but also on the moral and religious people who disdain the pagan people, while doing many things that show they don't trust and love God. That list in 1:29-31 includes things like "greed," "envy," "gossip," unloving," "unmerciful." Has any of us been as merciful and loving toward others as he or she ought to be?
So in terms of God's wrath, no, there's no difference between an intentional sin and any other sin. That's actually good news, since God's kindness extends equally to those who are redeemed from "bad" sins, like murder, as it does to any other offense against God.
But some sins are worse than others in terms of their effects on people. Paul hints at that in Romans 1:32, "they not only do them but give approval to those who practice them." Intuitively, we know that intentional sin is worse because it shows a decided disregard for God and His law. This seems to be the state of humanity that prompted God to destroy it with the deluge:
The LORD saw that the wickedness of man was great in the earth, and that every intention of the thoughts of his heart was only evil continually.—Genesis 6:5 (ESV)
Paul, in Romans 7, labels the "intention of the thoughts of his heart [to do] only evil continually" as "the flesh". Despite intending to do good, he finds himself in a struggle with his own intentions:
So I find it to be a law that when I want to do right, evil lies close at hand. For I delight in the law of God, in my inner being, but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members. Wretched man that I am! Who will deliver me from this body of death? Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin.
There is therefore now no condemnation for those who are in Christ Jesus. For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit. For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. For to set the mind on the flesh is death, but to set the mind on the Spirit is life and peace. For the mind that is set on the flesh is hostile to God, for it does not submit to God's law; indeed, it cannot. Those who are in the flesh cannot please God.—Romans 7:21–8:8 (ESV)
Whether Paul is speaking of his life before or after conversion is an open question, but either way the answer to this question remains. Intentionally sinning tends to draw us away from God. In that sense, the consequences of sin are worse than unintentional sin.
Our hearts are deceitful, so we have a strong urge to justify ourselves. ("I didn't mean to hurt her feelings and she's super sensitive anyway. What I did wasn't that bad.") We must remember that in God's eyes sin is sin. We don't get a pass because we sinned unintentionally.
On the other hand, there's no better way to shipwreck our faith than to continue in a life of intentional sin.