Ok, I took it one step further. Remember, the original Scorpion has vertical nacelles, the perfect combat arrangement. By forcing the warp bubble to form on the z axis instead of the y axis, the shield output mode (y axis generation) is not effected, therefore you get maximum shield efficiency. This is important in a warship, less important in an explorer. Let me explain my viewpoint a little better.
Explorer: maximum speed and warp efficiency needed. Nacelles must sit high, and be canted upward or horizontal. The higher the nacelle to the centerline, the higher the warp efficiency. Hence maximum warp speed. This configuration greatly effects shield output, lowering its strength and recharge capability. Examples would be the Constitution, Excelsior, Ambassador, Galaxy and the Sovereign.
Mixed mission: Centerline configuration, low nacelles along the lateral axis. Good balance of warp efficiency and shield efficiency. An example would be the Steamrunner or the Okinawa.
Combat: Maximum shield efficiency required. Nacelles must be as low as possible, positioned up to and including a pure z axis, below the lateral centerline of the vessel. Examples would be the Miranda, Nebula, Norway, Saber, Akira, Defiant and the Centaur.
Variable/Mixed: this is a special category. Either ships are configured with low and high aspect warp nacelles (two sets) or variable geometry nacelles to facilitate either higher shield efficiency or higher warp output. Examples are the Intrepid, Constellation and the Prometheus.
Now, originally, at least by my contention, you could have either fast speed (high) or strong shields (low) but not both. Then they came up with two sets of nacelles. One set would be maximized in output depending on need...higher set for high speed, lower set for higher sheilds. This was good, but not the most efficient setup, as the other set still lowered effiiciency in either mode. Finally, they came up with the solution...variable geometry. This allowed the nacelles to be moved above or below the centerline. Though a weaker mount at the rotation point, this seemed the best comprimise of all.
Now, with this ship I had an idea...why not give it the best of both worlds? It has horizontal configuration warp nacelles...not as good as the vertical mount, but the difference is not that significant. If you could move the nacelles, however, up or down...say 15 or so degrees up, and 30 degrees down, you get the right flexibility needed. So, in combat mode the nacelles are down 30 degrees. In cruising mode, they are horizontal. When the ship gets ready to jump to warp, they move up 15 degrees. I am posting the pics of the ship with the nacelles down 30 and horizontal, I will create a set with them up as well, and post those pics when available. Let me know what you guys think of this idea.