As kak has roughly the same key bindings as vim, if you found vim unbearable, you'll have problems with kak, too. However, I'm not sure what issues you think of

As kak has roughly the same key bindings as vim, if you found vim unbearable, you'll have problems with kak, too. However, I'm not sure what issues you think of, I've used vim/kak with a qwertz layout without problems. Just re-assign äöü.