Here is a way to encompass agility into a IMTU:
As far as computer DM's go, if the missile has laser coms, and the launching ship (or hand off to a control ship), has enough laser com antennas to control the salvo of missiles then the controlling ship's computer is used for the DM, however the distance from the control ship to the missiles imposes a sluglish response time. Reduce the effective computer level by 1 for every .5LS distant the missiles are from the controller. Minimum level is whatever level computer is on the missile. This causes you to send a controller missile or a few with the salvo, perhaps one in every six missiles needs a computer. Ditto for EW missiles, no warhead, instead has a EW suite and antennas (folding). Think Honor Harrington combat descriptions before deploying grav coms on the missiles, the tac officer programs the pen aid birds and specifies targets before the salvo engages the defenses, the time lag makes it impossible for the tac officer to do any real time corrections, everything is covered by the embedded computers on the missiles. While the defending tac officers on every ship gets to make real time updates, however the salvo passes through the entirety of the defense envelope in perhaps 3 seconds, so only time to give one order per tac officer.
Now how do we play that in Traveller? If both sides of the battle are players, and they designed their ships and weapons themselves (FF&S rules for the designs I am assumming, as they give way more flexability) then the referee can set up three maps, one for himself and one for each player faction, track all forces on the ref's map, only give contact info to players as they earn the intel. Fight the missile engagements acording to the capabilites the players designed into their ships and weapons. Ref establishes CEP chart by tech level defined as a circle of X diameter at .1 LS for each TL or range of tech levels. Example: TL 15 weapons (beam) have a CEP of 10m at .1LS however use of thrusters or attitude adjustments makes it 10 times worse per g applied: 1g = 100m, 2g=1km, 3g=10km, 4g=100km, 5g=1000km, 6g=10,000km (pick your own numbers to make agility use have the effect on weapon accuracy that you perfer.) Hit chances are per shot. If the target is still on the dot and the CEP is smaller than the area of the target, then all shots hit "spot on the dot"). If the target is no longer on the dot but the CEP still covers the area the target is in, then per the ratio of area of target/area of CEP shots hit "spot covers the dot". If the target has managed to get off the dot and the CEP is smaller than the enemy hull area facing, then all shots miss "spot misses the dot". What do I mean on the dot? Your position was predicted to be (X,Y) and when the shots arrive you are at (X,Y) or close enough that parts of your hull are at (X,Y). Not on the dot: you have changed your actual position by the amount of your hull length+enemy CEP, causing all shots to miss.
For large battles, first play a one on one using standardized ship classes, calculate ranges and agility needed to get off the dot results, and the ranges where regardless of agility all results are on the dot. Note these ranges on the data sheets for each ship class. Assume the commanders of the ships understand these ranges and the enemy CEP ability. Closing to engagement: Each side tries to maneuver such that if they can get off the dot while the enemy is on the dot (CEP is big when you are using 6g agility), then they are happy to attrit the enemy for free unless there is some fixed position that they are tied to (defending a high port or in system infrastructure). The side at disadvantgage closes the distance to bring the other side back onto the dot. Fight a few rounds as each force jockeys for an advantage, till both sides are "spot on the dot", or one side tries to break away. Obviously with ROF default of 10 firings per half hour, but rules allow beefed up weapon systems that might put out many many more shots than that. Say a weapon could fire at ROF 900 or one shot every 2 seconds, but consumes all your agility energy allocation, the enemy being "spot on the dot" is when you will use this. You get to fire this weapon 89 times before all guns fire, pray you hit something good before they can shoot back.
