AI Artillery behaviour is my biggest concern

so far played some SP schenarios. Far better than vanilla in my view. Biggest concern is the artillery when a division is attacking. Even putting it at the end of the line in the deployment phase or directing the battery manually (unTCd because otherwise the guns won't fire) to unlimber during the attack into a spot where
- it is far enough away from the enemy
- has free LOS unto the enemy
it almost always starts to limber the guns imediately again, moves forward, detects it's too close, moves back, unlimbers, limbers, moves forward and so on.
I understood there is not a position in a cornfield block LOS and thus the AI wants to move.
Is there anything I can do about it?
Making an "aggressiveness" value lower in the unit tab , so that it stays where it is and starts firing?
Finding a good location for artillery and developing the attack around it is one of the fun parts for me...
Or can you perhaps tweak the AI to be less critical when analyzing its position?

TC-d battery does fire if the position meets conditions of LOS and those implemented in AI...
The thing is that LOS is not tweak-able and often what you think should be visible it really isn't...
you may also experience that guns wouldn't unlimber too close to the enemy - especially cavalry... actually has to be quite far from it.

There is an entire section in the KS Mod Manual, (Manuals sub-folder of the KS Napoleon Mod), that covers artillery, the dos and don'ts.  To quote part of it:

Artillery
With regards to micromanaging the artillery batteries, our advice is don’t. The most common error
made by players is trying to move the guns too close to the action, or trying to slightly adjust their
direction of fire or position on the field. This almost always causes the guns to stop firing and the player
pulling his hair out by the fistfuls.
In general, the battery commander is far better in finding a proper spot for his guns than you. Allow him
to find the right place. Your job is then keeping the infantry out of the way so the guns have a clear line
of fire. Note, in rolling or hilly terrain, there may not be a very good spot due to line of sight
considerations. That’s just the way it is. Not all battles can go as planned.
Support the guns with cavalry or infantry. Alone, the guns are easy prey to marauding cavalry. The AI
will assign a battalion for this task automatically. But if enemy cavalry is in the rear areas, then leaving a
regiment of friendly cavalry nearby may be good insurance.

"it almost always starts to limber the guns imediately again, moves forward, detects it's too close, moves back, unlimbers, limbers, moves forward and so on."

Chris Crawford (who wrote Patton vs. Rommel) first described this AI behavior way back in the '80s. It happens because a unit 'wants' to attack, moves forward, performs another analysis, decides it's too close, or outnumbered, and retreats back to where it started where it repeats the loop all over again.

Artillery can definitely be difficult. I still struggle with fully understanding it sometimes. A part of that is due to the line of sight code that cannot currently be changed. In general I put my artillery commanders on all out attack or attack when I want them to be trying to find a spot to set up and shoot, and often I put them on this stance when I start marching on the road at the beginning of games. I find the lower defensive stances to make them much too cowardly and they never set up in range (although this behavior can be useful as well).

When they're doing something silly, or taking too long to get themselves set up and firing and I don't have time for them to be wasting I will TC the artillery commander and order them myself to deploy how I want them. Once they start firing I'll usually un-TC them so they can react to threats. Once they're shooting the AI will most likely keep them there until they have no more targets.

It's tricky to judge the ranges and line of sight, but what's helped me is thinking of everyone being much smaller. As far as the line of sight is concerned the spites could be half their current size or smaller and still might be too big. This can lead to situations where it seems like you can see a unit clearly, but they're actually behind a small berm that they can hide behind.