I've am trying to create my own version of BattleMod (from a local copy of BattleMod).  My idea was that experience would improve the accuracy, evasion and "damage control" (shield recharge, repair after phase and repair after battle) rather than increasing the health and Maximum shields of the ships. To try to compensate for this I've doubled max health and max shields (which is on top of the increases built into BattleMod) and removed the 20% manpower damage bonus (I think).

I edited SimulationDescriptors[Ship].xml in my mod as follows (changing how ship levels work; examples shows rookie, rookie II and legendary to show default, first promotion and max effect):

<SimulationDescriptor Name="ShipLevel01" Type="ShipLevel" IsSerializable="false">

        <Modifier TargetProperty="MaximumHealth" Operation="Percent" Value="1.00"     Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="MaximumShield" Operation="Percent"  Value="1.00"  Path="ClassShip/ClassSectionCore"/>

    </SimulationDescriptor>

<SimulationDescriptor Name="ShipLevel02" Type="ShipLevel" IsSerializable="false">

        <Modifier TargetProperty="MaximumHealth" Operation="Percent" Value="1.00"     Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="MaximumShield" Operation="Percent"  Value="1.00"  Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="Evasion"       Operation="Addition"  Value="0.01" Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="Accuracy"        Operation="Addition" Value="0.01"   Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="RepairAfterPhase"      Operation="Percent"  Value="0.01"  Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="RepairAfterBattle"      Operation="Percent"  Value="0.01"  Path="ClassShip/ClassSectionCore"/>        

        <Modifier TargetProperty="ShieldReloadPerPhase" Operation="Percent"  Value="0.01"  Path="ClassShip/ClassSectionCore"/>    

    </SimulationDescriptor>

<SimulationDescriptor Name="ShipLevel10" Type="ShipLevel" IsSerializable="false">

        <Modifier TargetProperty="MaximumHealth" Operation="Percent" Value="1.00"     Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="MaximumShield" Operation="Percent"  Value="1.00"  Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="Evasion"       Operation="Addition"  Value="0.10" Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="Accuracy"        Operation="Addition" Value="0.10"    Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="RepairAfterPhase"      Operation="Percent"  Value="0.10"  Path="ClassShip/ClassSectionCore"/>

        <Modifier TargetProperty="RepairAfterBattle"      Operation="Percent"  Value="0.10"  Path="ClassShip/ClassSectionCore"/>        

        <Modifier TargetProperty="ShieldReloadPerPhase" Operation="Percent"  Value="0.10"  Path="ClassShip/ClassSectionCore"/>            

    </SimulationDescriptor>

But I can't tell if the settings are actually working in the battles. Is there any way to get detailed battle logs that actually show accuracy per shot, repair after phase, shield recharge, etc? 

Answering my own question, I am just setting the values for rookie II to maximum (one at a time) and then assessing the results in the end of battle analysis. Obviously a debugger that showed every shot would be better but I should be able to tell roughly if the settings are doing something.