How much harder is it to get published in a top-tier journal (ACM, IEEE) compared to a small second-rate conference?

Is it an unrealistic goal to try to publish my 1st paper in the #1 journal in the field?

Is it likely such a journal will accept my paper if I am proposing a hybrid method that combines methods used by other papers? Or do I need something completely new and ground-breaking?

Does the fact that the 1st author will be a student (undergraduate) will reduce my chances?