At an equal technological level (which is the case), the larger ships wins, easily.
Meaning - Voyager gets fried against the Enterprise.
Why? No one on here has given any evidence as to why. The only thing people keep saying is that a larger ship has more power and more firepower. That has not been proven. These ships were built with exploration in mind, combat abilities are based on defense. The only time ships were used with true battle fashion were during the dominion war.
No one has given any proof that more power isn't just a misconception.
In warships size MATTERS.
More power, heavier weaponry.
There's no such thing as a magical "fit everything that makes a cruiser into a destroyer".
This is, of course, true of the real world, as well. Nobody would use a battleship if a destroyer could bring the same firepower to bear (by using any design philosophy you'd care to think about).
Much like it's true in the trekverse, as well - I take it you see the difference between a runabout and the enterprise or between a bug and a heavy dominion battleship.
Plus, Voyager was shown as having an equally large percentage of amenities as the Enterprise (crew quarters, etc). It's not even built with a Defiant-like philosophy.
PS - Do try to read the posts.