I created a mod that will apply visual effects to all characters involved in a conversation when your main character's influence with one of your companions or her alignment (lightside shift/darkside shift) changes. This way you can see right away what replies cause influence/alignment shifts, because it's not always clear.
The visual effects are applied to all characters involved in a conversation, since you never know who will be in camera focus (on-screen) when the change occurs.
I couldn't find out how to apply the original visual effects that are displayed when your alignment changes (hardcoded?), so I use the following visual effects:
Influence increase: Valor VFX
Influence decrease: Force Body VFX
Lightside points: Heal VFX
Darkside points: Poison VFX
The effects stack with each other, so if your character says something that both increases/decreases his alignment and influence, 2 effects will be displayed simultaneously.
Download and extract these files into the Override directory: