I might've said karim didn't deserve to die like that, and I still do stand by that, but his death isn't completely hamfisted (he did get "finished off" by friday, after all). Friday isn't a good person, though he does have some concept of honour. I feel like Karim died a hero's death, in the end. The author could've used him further in the next season, but chose to use him as a motivation to further scale power levels and introduce motivated enemies, which I can respect.
It remains to be seen if they can also handle the newly introduced characters well going forward. Given their track record so far, I'd say it's likely, though I suspect there are going to be a few more hamfisted moments here and there to get the plot furhter along.