Different machines don't matter, its still working the same muscles. I don't like the amount of reps you are doing either. For mass building you want to stay between 6-8 reps for 3 sets. For cutting (fat loss) or fitness you want to stay between 10-12. 20 reps is too much and only 2 sets is not enough. You want to stick to 3-4 different exercises (so 9-12 sets) for each body part.

Working your abs does nothing, the only way to get a 6pack is to lose fat which comes from either cardio or more importantly your diet. Crunches will strengthen your abs (I think that is mostly for stunt people and athletes though) but will not help with actually showing a 6 pack.

I personally do not like machines, they sometimes allow for too much cheating. I would rather see more dumbbells and barbells in your exercises because they work the muscle more. Machines IMO should be used for rehab because they work the muscle with weight but there is little to no risk of injury.