As long as we're talking of Hannelore encouraging him and not us. I'm not a fictional character <looks around> at least I hope I'm not. (If I am, my writer better hope I never find a way to get at him.)
I actually liked Sven when he was first introduced, and thought he was going to be good for Faye (which he was, but in a kind of fires from hell way I wouldn't wish on anyone that's already been through as much as Faye has*). I can trace my dislike of Sven to three comics (which I'm not going to link at the moment):
First, when Faye asks for a date and he shuts it down
Second, after he has sex with Riversmith and, instead of facing up to Faye, just as with Dora, he tries to hide it. (Thanks, Lydia)
Third, when he gets angry at Faye at Hanner's Snow Block Party.
And, although, as I said, I wouldn't wish it on anyone**, I suspect it's going to take a little flame to truly change his ways. Which, by my estimate, will happen only when he makes peace with Dora, which will involve actually apologizing instead of thinking pretend-dates will do the trick. As opposed, of course, to preening his feather about how good a lay one of her friends, former by then, was.
* No, I don't excuse Faye from all her behaviors due to 'issues,' but this was a little much. Although I've complained during the process, it's actually pretty impressive she's picked herself back up. Some credit to Angus, a person who, whatever his faults, is responsible and does take his screw-ups seriously. If you think about it, Jeph put him through the same tests he did Sven, only both at the same time. (listens for the crash as thread derails from the Legion of Angus detractors boarding all at the same time).
**this is supposing the Bianchi parents really are irresponsible wretches.