For instance 50 soldiers come for you.
Bad skills ? You see "10-200 peasants"
Average skill ? "63-121 soldiers withs words and medium armor"
Good skills ? You see "94-118 soldiers with swords, medium armor and seems to be rookies"
If it were truly 50 soldiers in the enemy army, I would prefer
Bad- you see 25-75 people
Average- you see 35-65 melee troops
Good- you see 45-55 swordsmen with chain-mail armor
Excellent (Magic)- you see 50 soldiers with +2 longswords, and light chainmail armor
Also, instead of seeing a range (45-55) you would only receive one number, and based upon how good your scouting ability, would have to deduce how close your number might be. I recommend a linear probability of each number as opposed to a bell curve, although I wouldn't mind a bell curve.
I mean, a bell curve might make it too easy, but more realistic to be certain. Probably a shallow bell would work, where the center is only twice more likely than the edge (thats a really shallow bell)
For instance, on linear probability, and average scouting ability, you might "see" 35 melee troops. You would have an equal chance to see 50 melee troops. With a bell curve, you would be at least twice as likely to see 50 soldiers than 35 ... yet off estimates like 35 and 65 are still possible.
If 100 archers are in enemy army ...
Bad- you see 50-150 people
Average- you see 75-125 ranged troops
Good- you see 90-110 archers with longbows and leather armor
Excellent (Magic)- you see 100 archers with Yeoman Longbows and Studded Leather Armor
Premise is that Bad's worst case scenario is 50% off, while Average's worst outcome is 25% off, and Good's worst outcome is 10% off. In addition to more details being given for Good or Excellent scouting. Probably works best with a bell-curve ... so that no matter the rating its quite possible that the numbers are accurate, however it is also possible that the number is way off (50%). In this way, with a bell curve, you begin to expect any skill-level scout to be reasonably accurate, and you might get in the habit of using the cheaper "bad" scouts. As in, it would be relatively rare for a Bad scout to actually be a whole 50% wrong, and as such something Shocking/ Suprising yet not something that is unexpected on principle ... since they ARE "bad" scouts.
The most important part of this system, is that you are only given one number, and based upon the Skill-level of the scout, you have to determine how reliable this information is. It might be possible to scout out an army multiple times within one turn, just not by the same agent.