If it was a line of sight issue the unit would not have been "engaged". In fact one of the best ways to check if a line of sight issue is occurring is to check the unit status. If a unit is within range of the enemy and is not firing and the unit is "resting" it is definitely a line of sight issue. If it says they are engaged but you don't see any casualties, it is most likely that the unit is out of ammo. If they are engaged and also not taking any casualties, then either the enemy unit is also out of ammo, or is firing at some other unit. But it will still say engaged because your unit is engaged, even though they are out of ammo. Again, if this was a line of sight issue it would not say "engaged"
Also I advise getting over your dislike of micromanaging. Micromanaging is one of the single most effective abilities when it comes to defeating the AI. When you leave your officers and troops under AI control and order them to attack via stances/command map/couriers what you're essentially doing is ordering the AI to fight itself, as its controlling your troops as well as its own. Thats a lot like watching a computer play itself in tic tac toe. Its fun to watch them try to carry out your orders, but you yourself aren't really doing anything but watching.
Also most scenario's require the capture and holding of objectives for the majority of the points needed to achieve a major victory. These objectives, once captured, require a certain number of troops and an officer to remain within range of the objective to continue receiving points from it. If the officer, or troops move to far away from the objective you will lose control of it and have to reaquire it, which resets the timer on the objective. This can be annoying if your dealing with an objective with a long duration(Some are as long as 20 minutes.) The AI is notoriously bad at maintaining objectives because officers are constantly running around the battlefield like a chicken without a head and they never order their troops to just hold the objective. Also, being plain honest, there are scenario's in the game that are just plain unwinnable if you just let the AI do the fighting for you. It isn't aggressive enough, it doesn't particularly care about holding objectives(the heart and soul of winning most scenario's)and its tactics can often be downright stupid.
Also there are a number of strategies and tactics that give you a distinct advantage over the AI once you understand its weaknesses and tactical deficiencies. But almost all of them require heavily TC'ing your troops and micro managing because if left under AI control, your troops will never exploit these weaknesses because you are letting the AI control them, and the AI obviously doesn't know its own weaknesses.
Ive been playing this game for nearly 3 years. There is virtually nothing I do not know when it comes to the gameplay of this game. Ive discovered all of the best strategies and tactics for beating every scenario in the game. There are very few people alive who know this game like I do. Some of my tactics are cheap, some are abusive of the game mechanics, and many of them are downright ahistorical, but above all, I can teach you how to win.
I can teach you everything about this game if you're willing to put in some time to learn. Everything Ive learned about this game in nearly 3 years of playing, every mechanic, every exploit, every formation, every loophole and the best tactics and strategies for beating every scenario in the game I have poured into my Scourge of War series on youtube. There is nothing else like it on youtube because no one else on youtube knows the game like I do. I invite you to watch it. It is long. Its many hours of footage and will take a long time to get through. Ive held nothing back, ive left nothing out. All my knowledge is there for the taking.
Brigade series -
https://www.youtube.com/playlist?list=P ... NHeghO9XR5
Division series -
https://www.youtube.com/playlist?list=P ... 62TjfkoQZ2
Corps series -
https://www.youtube.com/playlist?list=P ... v-cRiWTtlQ
Full battle series -
https://www.youtube.com/playlist?list=P ... SFtSRagqF2
(This is still in progress, however, Quatre Bras, Ligny, and Wavre are all complete. Only Waterloo remains, and Il be starting it later this week.)
The Grog Toolbar Demystified series -
https://www.youtube.com/playlist?list=P ... LGXBt9GRHx
(I highly recommend dumping the stock toolbar for the Grog toolbar. The stock toolbar is terrible and no one who plays SOW with any kind of seriousness uses it. The Grog toolbar is superior in everyway)
Here is the download link for the grog toolbar:
http://www.norbsoftdev.net/forum/waterl ... olbar-grog
The rest is up to you if you really want to learn everything about this game.