Unity Advanced Shader Help

I am creating a videogame in Unity. Every sprite is rendered with a Sprite Renderer with a Material that has the CornucopiaShader.shader. The problem I have is I want to limit the max brightness (or color) of the sprite to just be a normal image of the sprite regardless of the power of how many point lights are hitting it, the intensity of the lights, and also the ambient light in the unity scene. When the intensity of the lights hitting the sprite is below that max brightness level I want it to act like a normal lit sprite and be black if no lights are hitting it, and be half lit up if an intensity of 0.5 is hitting it etc, and everything in between like normal. Problem 1: In summary if three lights at say 5 intensity hit the sprite, I want the sprite to just look normal brightness of 1 and not flushed out white with light.

Since the player can rotate like paper mario and switch sides the current shader code acts that way, and also currently light that hits from the backface should also light up both sides like it currently does in the shader. Problem 2: But another problem I am having, like is seen in the four images I have included is when I flip the player, the intensity changes.

I have been trying to figure out these two problems for 3 days straight and cannot figure it out.

Picture 1

Picture 2

Picture 3

Picture 4

 Shader "Custom/CornucopiaShader" {

 Properties{
     _MainCol("Main Tint", Color) = (1,1,1,1)
     _MainTex("Main Texture", 2D) = "white" {}
     _Cutoff("Alpha cutoff", Range(0,0.5)) = 0.5
 }

 SubShader{
     Tags {"Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" "PreviewType" = "Plane"}
     Cull Off
     ZWrite Off
     LOD 200
     ColorMask RGB

     Blend SrcAlpha OneMinusSrcAlpha

     CGPROGRAM
     #pragma surface surf SimpleLambert alphatest:_Cutoff addshadow fullforwardshadows alpha:blend
     #pragma target 3.0

     #include "RetroAA.cginc"

     sampler2D _MainTex;
     float4 _MainTex_TexelSize;
     fixed4 _MainCol;

     half4 LightingSimpleLambert(SurfaceOutput s, half3 lightDir, half atten)
     {
         half4 c;

         c.rgb = s.Albedo * _MainCol.rgb * (atten)* _LightColor0.rgb;
         c.a = s.Alpha;

         return c;
     }

     struct Input {
         float2 uv_MainTex;
     };

     void surf(Input IN, inout SurfaceOutput o) {

         fixed4 c = RetroAA(_MainTex, IN.uv_MainTex, _MainTex_TexelSize);
         o.Albedo = lerp(c.rgb, c.rgb, c.a);
         o.Alpha = c.a;

     }
     ENDCG
 }

 Fallback "Transparent/Cutout/VertexLit"

}

 #include "UnityCG.cginc"

 #pragma target 3.0

 fixed4 RetroAA(sampler2D tex, float2 uv, float4 texelSize){
     float2 texelCoord = uv*texelSize.zw;
     float2 hfw = 0.5*fwidth(texelCoord);
     float2 fl = floor(texelCoord - 0.5) + 0.5;
     float2 uvaa = (fl + smoothstep(0.5 - hfw, 0.5 + hfw, texelCoord -     fl))*texelSize.xy;

 return tex2D(tex, uvaa);
 }