Total aircraft length is actually secondary. Look at the F-22 - The horizontal stabilizers extend far beyond the actual body. What matters is the volume of the airframe and the associated space for fuel, weapons, and whatever else you need to accomplish the mission. Hence my aim was to design something in the order of magnitude of the F-22, but with increased airframe volume. To do so, I chose wide spaced engines and tandem bays, wraped in a blended-wing-body airframe - Imho a very efficient layout.
I think the exhaust nozzles in my concept are actually hidden pretty well. Additional factors come into play if you want full TVC (pitch/roll/yaw) - tradeoffs! Btw, we don't even know yet if F-47 will feature TVC at all. This will definitely effect the shape of the nozzles and the rear of the airframe.
Length has to be reported from tip to tip just like our height in personal/medical records.
All things are connected & matter at their place.
In F-22 there is a reason for stab extension which i already mentioned - to hide nozzles from side & allow transpiration cooling.
Length also gets affected by wing shape, area as part of design criteria.
So the aircraft length is not secondary.
Ofocurse volume matters, if weapons longer than 4m are desired to be carried internally then obviously it will be voluminous & lengthy.
We need space for DEW system also.
But we can't increase volume randomly as per our wish in XYZ axis. The sonic area rule has to be followed otherwise sonic drag will increase limiting supercruising & max speed.
The volume/weight cannot exceed desired ATWR (A/c Thrust to Weight Ratio).
If XA-10X engines give 50% more thrust then for same ATWR assuming same density the airframe can be expanded cuberoot(1.5) = 1.1447 times or 14.47% in XYZ axis.
Imagine F-22 split for 2 tandem bays like in Su-57. So we might have 4 belly bays. The width might increase by say 30%, the length might increase by 20%, the height might increase by 10%, so volume/weight might increase by 1.3x1.2x1.1=1.716 times or 71.6%, so the engines will also have to deliver that much more thrust - 156x1.71=267 KN wet thrust each, 116x1.71=198 KN dry thrust each.
IMO a bigger 6gen jet w/o rudder should have TVC, not for aerobatics or gun-fight, but for control authority. The F-22's nozzles move also during normal flight, t/o, landing. It has become a normal part of an agile fighter with rudder, then w/o rudder it would become a need.
It is totally upto enthusiasts if they wanna make drawings & CADs purely for fun or as realistic as possible.
Someone should make aircraft manufacturers aware of this
Makers are aware, enthusiasts may not be.