11-April-2020: I'm gonna go ahead and say the "design" phase is done as I can change it and change it until the tribbles come home so here's the physical layout of the Mustang. I want the Mustang to be a very small, powerful and fast ship meant to be a localized to system defense such as the Terran system, and multi-ship Fleet Missions. Similar to US Navy Carrier fleet operations. A deep space exploration fleet can consist of at least 2 or 3 Mustang class vessels. Prior to the mission fleet arriving to a certain location, as many as three Praetorian class vessels will arrive prior to scout and reconnoiter the system. Should the ships be attacked or witness hostile factors, they will either suppress/eliminate that threat or exfiltrate to report on the situation. 

In combat situations, the Praetorian class is very suited to attack missions and defense missions. Usually, many to most command level Stafleet academy graduates are initial stationed on Praetorian Class starships. The shorter missions and localized stations mean new command officers can gain quick experience before moving on to larger vessels. Many young officers will get "the chair" time as officers as low as Lieutenant can command the Mustang Class vessel for short missions. However, some officers choose to make this class of vessel their entire careers. Many officers are more suited to the military, scout and defense side of Starfleet. Although Starfleet's main function is exploration and humanitarian missions, Starfleet will always have a main core meant for militarized defense and war-making.