"D" for me.
It is a more original design, albeit cheaper in some ways - the lack of nacelle adornments, and even the snap-lock look of where the nacelles snap into the engineering hull for easier assembly or whatever the reason was being one of them. (which is far easier to spot on the blu-ray, but even then...)
The phaser arrays are so much fun to think about. Each turret node can be angled in roughly 300 degrees (not unlike what the TOS/film 1701 could do, save for lack of nodes), with the potential of multiple beams from each array - though instead the f/x shots always show two beams from either side converging from an ultimate single node. Possibly due to the power level needed. Each nacelle pylon has an array, both top and bottom of saucer has an array, etc...
The ship isn't as photogenic from some angles, but it's a spacecraft and the laws of terrestrial physics and pesky gravity don't apply and I never cared for it when they showed the ship inside Earth's orbit, or any planet's orbit.
That said, it looks perfect from other angles, and can indeed carry the visual cue of zippy speed despite the oblong saucer betraying it in other angles - which initially (in 1987) gave me the impression the designer saw the old ship model, imagined what it would look like if sat on by a bored elephant, and penciled in the rough draft as a result.
The separation issue - the idea was dropped because the time needed to separate allegedly hampered the drama. In the few times the capability was used, the drama still seemed fairly ratcheted up. But how many plotlines could make appropriate use of the concept before it got diluted down? Plus, I suspect some dislike the shape of just the Engineering hull. But, again, aesthetics in outer space. After all, look at the Borg cube as the ultimate example and/or po-faced* parody of the idea of ships in outer space having to look aerodynamic and aesthetically pleasing... though to an extent, the latter is going to have to be the case for entertainment purposes. Showing an "ugly" ship, however "ugly" can objectively vs subjectively defined as - of course - would probably nullify some of the drama as well.
* as in "parody not meant to be a joke in a comedic sense"
Best of all, any initial nitpicks of the ship in 1987 melted away in 1994 when seeing GEN on the big screen. The design of the model really lent itself to the big screen with ease.
I do adore the "D" for everything that it does.
The "E" I'll go back and forth on.
Despite the TNG movies ditching the Galaxy class, regardless of how cool it looked, nobody's going to blame them for doing a new model design and - yeah - all in all, it's pretty solid.
It looks sleeker, due to its length of course, but is clearly an update of the "A" with bits of "D" added. Nacelle adornments do look terrific and are artsy, but that lower hangar/storage bay in the aft doesn't impress, though if you look at the "D" blueprints they have storage bay doors shown as well. Shame they never got used... if the actual TNG movies had been stronger, I could have a field day headcanoning or wishing to see more of the ship. But a movie is not just pretty visuals, which can only serve to complement strong plotting and can't really supplant it. (That said, seeing the ramming scene in NEM was fantastic and managed to be deservedly gripping, even if surrounding plot elements were too many chucked in...)
The yellow deflector dish is a break from the mold, and it grew on me. But I did miss the blue...
Of course, the "E"'s nacelles also break the other mold, that of how the technology improved for several decades and yielding smaller nacelles. I suppose it made enough difference to have longer ones generate the field via less power or whatever treknobabble... then again, how "All Good Things" added a third nacelle and how VOY did the flappy-wings nacelle design to counter the fabric of space in the dumb "55mph but in outer space" episode that was promptly glossed over like a cheap arcade token, not quite unlike the one you found last week when cleaning up the basement and realized how much fun it was in the 80s going to arcades and then wondering why you'd misplaced one...
At the end of the day, I still prefer the "D".
