I've always preferred the pointy nosed shovel-like primary hull shown in the concepts more than the blunt nosed spoon-shaped nose of the final version of the Intrepid class. I especially love the sketch where the primary hull looks flatter and wider, than what was chosen in the end.
I think it was a good thing that this design element was used for the Nova class and the Prometheus class.
By the way, Mr. Sternbach, if you happen to read this, I want you to know that the Nova and the Prometheus are among my favorite canon Starfleet designs, up there with the Sovereign class. They play a significant influence in my designs, and the amount of detail that you put into your sketches has influenced me to try to do the same in many of mine (well, at least the ones I post)

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I'd have liked it better if the sharp nose and the wider looking stance of the saucer, like in the bottom concept sketch in the image below, and used that with the secondary hull that was used for the final design:
I also like how the secondary hull starts to become thinner in the top concept sketch, and how it transitions from thicker to thinner by a section of the hull curving, as opposed to having a section of the hull that has a faceted look.
I don't know if I like it as much as the simpler overall curves of the secondary hull of the final design, but it makes for an interesting design element.
And I like how the front edge of the bridge and the edge of the fan-tail is rounded and curves better than how they are blunt in what we ended up with, like what is shown in the top image, and Calamity_si's model.
I think that the first model that they did before starting all over might have looked better had they used some of these design elements. I also have never liked how the first model looks taller, as opposed to being flatter, and more splayed out, like something fast waiting to take off.
The final thing I can't help but notice is that most of the concepts are have better phaser arcs, with aft dorsal phasers on the secondary hull. This interestingly enough seems to have been remedied for the model used in STO.
Oh, and by the way Calamity_si, your model of Sternbach's concept looks fantastic!

Your modeling skills have improved dramatically from what you had when you entered that Enterprise-F contest.