I think people on here are generally way too salty about "quitters". The thing is, I rarely saw anyone quitting in all the games I played. Sure, when it happens it's annoying, but does it really happen THAT often that there has to be a merciless crusade against anyone who happens to not be able to finish a game?
I am fine with karma penalties for leavers, but imo they are already harsh enough.
But even more importantly, if you want to maintain a well-functioning and fair system for karma penalties, the technical side of things has to be in order. Sadly this is not the case on BGA, there's quite a large amount of technical issues and hiccups all across the website. I am personally at 73 karma now and I don't type this post out of spite or anything, as I am not distressed by this, but I think it's completely unfair.
Not a single one of all my "leaves" was by choice. All of them were in live games, caused by technical issues with the website, or interface issues. Believe it or not, it really is. Maybe it is because I play on phone and tablet a lot (only on stable Wifi), and the PWA mobile version of the app / site is just not that great. According to BGA, there were no technical issues at the time, so my karma is not reinstated. Probably a lot of salty people won't believe me, but I am 100% sure I am not the only one who has this issue.
So no, there should not be harsher penalties, at least not BEFORE the platform is stable enough to support such an unforgiving system. People should be a bit more forgiving and understanding in general to other players. It's not the strong suit here. I ran into much more impatient people than people who leave.
The other poster before me is on to something here, that a lot of people who play here seem to be of the "hardcore" type, who take things very seriously, and are... how shall I say it.. extremely dedicated to the games they play and the correct resolving of scores and such. Nothing wrong with that, but there also has to be breathing space for different kind of players without the first kind of player being absolutely dominant, resulting in an uptight way of establishing rules and the way the platform is being managed. Especially in non-arena ranked.
Have some faith in your fellow players, give them some credit. You will receive back the generosity in some way. Isn't that the whole idea of karma?