First World War Campaigns - Optional Rules

[BigDuke66]

After having the experience from the Napoleonic and Civil War series that OR can have a big impact on the game play I wonder what should or should not be used in this series.
A quick glanced showed me that a lot of the the OR are turned On by default, should any of these be turned OFF?

Now about those that are not On by default:
Manual Defensive Fire/Automatic Defensive Fire
From the other series I ended up giving up on turn gameplay and switching the phased gameplay, is that also recommended in this series?

Optional Fire Results/Optional Assault Results
OK these two seem to make outcomes more predictable, in the other series I turned them ON, should it be done here too?

Locking Zones Of Control
Now this is interesting, in Panzer Campaigns the standard battalions can be split into companies, seems that this is not possible here and the manual explains:
"The purpose of this rule is to compensate for the inability to break down larger units into smaller ones so that continuous lines of defense can be constructed."
So with breakdown not possible here, should it be turned On?

Higher Fatigue Recovery
I had this turned On in the Civil War series after seeing the even low fatigue units can hit high fatigue area after a failed melee what basically turns them into fire-and-forget weapons that can't be sued for the rest of the game, further more the fatigue calculation looked strange as the unit took fatigue in an amount that should simply not be possible according to the calculation explained in the manual.
Now I have no experience how it runs here, any recommendations?

Counterbattery Fire
After seeing that a lot differs in the field of artillery compared to the Panzer Campaign series I guess it is OK to leave this OFF for the First World War while it seems mandatory for the Second World War.
On the other hand it's set by the PDT either to 0% and so isn't used at all or it has a higher percentage and so is intended by the scenario designer to be used, so turning Off seems to make no sense or do I miss something here?

No Low Fuel Effects
With so few units that are motorized the rules won't have a big impact but still why should it not be used?

Explicit Supply
Like with Counterbattery Fire OR it seems again to make no sense to turn it Off because according to the manual:
"When a scenario does not contain Supply Units, then this optional rule does not apply and the normal Resupply rules apply."
So either the normal rules are used or if supply units are in the scenario the rule should be used as the designer intended this. Again do I miss something?