I like the idea, and you did a good job on it.
But, when I imagine a refit of a ship, I think of using the original framework and only tweaking some parts and giving it enhanced tech. Less of the TOTAL overhaul the Constitution went through (which is only the case because of budget) and more of the minor adjustments the Sovereign went through (different nacelle pylons, updated hull-plating, etc.)
I'd imagine a refit of the Kelvin having generally the same dimensions, a new nacelle (but have it be about the same length and width), a slightly bulkier engineering (still same length, and have the shuttlebay unchanged), and probably a new bridge. I'll do a sketch to show what I mean.
Anyway, nevermind me, I like your ship and look forward to commanding her in battle.