For example; let's say the Caretaker dies, and the Kazon come to attack the now defenceless Ocampa. Janeway is urged by members of her crew just to leg it back home, and leave the Ocampa to die. Janeway refuses to stand idly by while billions die, and intercepts the Kazon attack group. They beat the Kazon, but the array that can get them back is destroyed by Kazon ships during the fight.
This way, you end up with Janeway being stranded because she was unwilling to allow billions of deaths, which instantly makes the character far more likeable and realistic.
Neither am I, but I can still figure that timer+bomb+array=End of problems. Janeway simply has no excuse for not realising this possibility. Hell, her whole crew is somewhat culpable in this, as no one suggested this to her!True but she may not be as tactically minded as a combat professional.
How? These guys would take an hour to figure out how to change a lightbulb. Do you really think they could figure out how to disarm a totaly alien bomb before it went off?There may have been time for the Kazon to disable the explosive as well.
And besides, you need only set it for a minute or so. Then you just slam on the warp drive, and leg it out of the area. Before the Kazon even arrive, the array blows up. End of problem.
And even if the Kazon could somehow get there, find the bombs, figure out how they work and then disarm them all within a minute or so, there's always the possibility of leaving one crew member behind with a trigger and a bunch of torps. As soon as the Kazon reach the array, boom.