So it actually looks a lot bigger than it actually is.
Except that it does not. It is
a lot bigger.
Just the coarse side view will reveal the massive warp nacelles, the humungous "head hull", and the sheer chord of those wings. The ship in the smaller of the two alternative views above is necessarily at least three times as heavy as the Galaxy
, assuming somewhat similar materials and construction techniques, and quite possibly ten million tons heavier.
is a flat and flimsy thing that is mostly empty volume - draw a box around it and there's lots of "wasted" volume between the nacelles and underneath the saucer. Draw a box around the Romulan ship and the amount of "wasted" volume is at most the same, and probably a bit less.