It's too bad there isn't anything solid on this topic but then it wouldn’t be much of a topic if we had the info.
I think the most obvious answer is likely correct, more engines means more power and more speed.
There would be one major advantage to having more than one nacelle, the work per engine can be spread out, implying a four nacelle design can maintain a higher speed with less wear per engine offering longer top warp duration or higher top speed, or a mix of both.
The reason we mostly see two nacelle designs is probably just as simple, diminishing returns at top warp speed offers little advantage to more than two warp engines unless a mission specifically requires it. We don’t see one engine designs because that’s a little too vulnerable and slow. As engineering improves the peak power of one engine would improve, but at the same time manufacturing would improve and make having more engines cost less to implement.
That fits with how the Prometheus probably would have been a rapid response Borg interceptor, needing every last bit of speed, where as the Defiant is more a strategically defensive platform since it is slow, but I suppose that’s speculation.
I think the most obvious answer is likely correct, more engines means more power and more speed.
There would be one major advantage to having more than one nacelle, the work per engine can be spread out, implying a four nacelle design can maintain a higher speed with less wear per engine offering longer top warp duration or higher top speed, or a mix of both.
The reason we mostly see two nacelle designs is probably just as simple, diminishing returns at top warp speed offers little advantage to more than two warp engines unless a mission specifically requires it. We don’t see one engine designs because that’s a little too vulnerable and slow. As engineering improves the peak power of one engine would improve, but at the same time manufacturing would improve and make having more engines cost less to implement.
That fits with how the Prometheus probably would have been a rapid response Borg interceptor, needing every last bit of speed, where as the Defiant is more a strategically defensive platform since it is slow, but I suppose that’s speculation.