Considering there is a high chance of warhammer 40k total war being in the works, this might become a very common source of frustration.

Direct line of fire units like gun units, refuse to shoot if the centre of the gun unit doesn’t have line of sight with the banner of an enemy unit.

So if there is a rock, or in this case house, or even tiny hillside blocking the sightline of the centre of your gun unit, the entire gun unit will not fire. 

Where this becomes a problem is if enemy units are super thinned out and wide, and their unit centre is either out of range, or behind a hill. Meaning your gun unit centre does not have line of sight with the enemy centre, while the other enemy entities might be fully in the line of fire, and yet do not get shot at.

oh yeah, and this might need to be fixed:

I can rip out the slide button

Can I also mention how these features are pointless?

A unit camera that, just does nothing except hinder your camera in a position that you can achieve by just zooming in

but worse, Tactical map mode, which for some reason removes your unit cards so you can't even position your units with ease, say for example in a siege battle, where you might want to use this map mode.

And I'd like to see a seperate option to give your ranged units default guard mode, but not your melee units.

I don't want my archers chasing things, but I do want my cavalry chasing things.