In 1987, it looked like they changed the saucer from concave to convex (interesting), added a bunch of windows (cool), shrunk the nacelles in half (iffy), then stepped on it to give it that flat look (ugly). They still kept aspects of the TMP enterprise - glowing deflector dish (though merged it with the radar style of the 60s original) and had nacelles glowing blue all the time, even when warp engines were active but not in use. Like a car engine in idle. (TMP onward glowed blue, from the inside only, and only when warp drive was activated.)
From the start, I liked the phaser arrays. That answered a lot of questions about space combat. I also liked the saucer separation idea, though if they're traveling at warp, as long as the Engineering hull doesn't go faster, the Saucer would still coast until met by a counterforce, which would cause it to slow down. Wish they used it more and, yes, one can have drama and some action/adventure too. It didn't need to be done every week but seasons 4-7 might have had a boost. Then again, they really changed the format of the show for season 5...
By "Generations", it grew on me. I adored the design, nacelles and pancake look and all. It grew on me. Immeasurably. And is iconic. The new interior lighting, while meant to hide knackered sets, made it all look far more formidable, powerful, and cool.
Its influence on the "E" - my favorite ship design - is palpable and impeccable in design, taking the best of "1701 refit" and "E" and making something as art-deco inspired as the 1979 refit as well as combining the best bits of "D". Makes me wish the TV show had the "E" design, that's how cool it looks, even with the secondary cargo bay at the rear of the Engineering hull. Or if the movies were superior than the quality of the TV show from which it stemmed.