I remember them saying they had to break down a wall in the studio to accomidate the TNG bridge which had to be larger because the ship was so much larger itself with over 1000 people instead of 400. .
Seem to remember it is the same width as TOS bridge, but between 2 & 4 feet longer. Rest of effect is due to lens choice and brightness.
Back on the question ... I don't think TOS ever looked futuristic to me (how could it? I saw 2001 when I was 7-1/2, not even anything NASA has done has ever looked as good), but at times it looked RIGHT, which is more important.
I ascribe that to dramatic cross-lighting, with a shadow side that REALLY fell into shadow. Finnerman pioneered it, but Francis pushed it harder ... I just LOVE the way the bridge looks when the air is cut off in DAY OF THE DOVE (y'know, the 'ship out, freak!' scene.)
The only bridge that doesn't date for me is the TFF/TUC/E-B variant, which just seems to strike a decent balance between credibility and visual appeal (at least if you avoid seeing the TUC sliders and other retro-groaners.) Colors and contrast on VOYAGER's bridge were good too, from what I recall, though I haven't seen much of the show.
The TMP bridge always read as a Lockheed lunchroom during a power outage to me.
The Abrams stuff is just looney tunes. Regardless of how bright the TOS set was, there was contrast, dark consoles, red trim ... The Abrams bridge is a Target store's cosmetics aisle, way too bright to spend time in or to be able to read a display w/o sunglasses ... and that's even before the lensflare madness enters the picture!