in the 1st situation, it is hard not to call a miss if you let the cue ball goes in-off that way. however, even it doesn't goes in-off, i may still call it a miss unless i feel that it was the best route to get the the object ball(s) and you have made your best attempt.
in your 2nd point, if your cue ball is no where close to the object ball(s) because it has gone in-off or hitted another ball on its way to the object, it is very unlikely i will not call it a miss.
although the miss rule is quite subjective to the referee, the general idea is that you have to let him/her knowing that you have tried your best to hit the ball-on.