USE THE PROPULSION MOUNTS TO REDUCE THE COST OF THE WARP CORE AND WARP NACELLE COMPONENTS
The reason for the mount system is to keep the size of the component proportionate to the hull size. IE larger ship use more space for said components.
USE ON YOUR SHIP DESIGNS:
2 Impulse engines
1 Warp Core
2 Warp Nacelles. (Unless the ship hull says you can use more)
Oh ya, one Last thing, if you dislike the mod thats fine, you can always make one yourself.