A person can do all of the above and still repent. Zina is no less haram based on frequency of prior indulgence. A person can commit 100 zina ,repent, and get married so as to not commit zina anymore. Are you saying god wont except that servants attempts of repentance and righteousness? Are you saying once you do wrong you have the go ahead to continue forever? God is the oft repentance accepting and the oft merciful.
Sincere repentance is the exception of course, but you need to realise that the vast majority of people who partake in these things don't even think they are doing anything "wrong" hence the need for repentance never factors in.
Another thing you need to realise is that if repentance is accepted the consequence of the evil remains, when our father Adam repented and his repentance was accepted by our Lord he didn't go back to Paradise but came down to the Earth.
Likewise if I am addicted to ography and my sincere repentance is accepted, remnants of the consequences of those addictions continues to stay with me.
Hence going into such a union while knowing it's haram with the intention of making it up for repentance is mockery of our deen, and if you go in completely ignorant like most people, you will never seek repentance anyway.