No, no, no....Dauntless was fugly, imo, and not Starfleet at all.
Here's what I think on the deflector area. It should be smooth, almost one with the saucer, with an area carved out just to house the deflector and quantum turret(if wanted). No Dauntless.
As for the engines, I still say something along the lines of the last batch. Those were freaking awesome.