CORE FEEDBACK
A core and negative difference between the Voicemod V3 and the Legacy one is that the Standard Voices on the Legacy version have the Mix Setting which, at least in my experience, is one of the most useful settings considering I use and change it all the time for different "effects".
OPTIONAL FEEDBACK
Another thing that I would like to add is although I can not talk for other people, I really like the Legacy's version availability to duplicate a Standard Voice to change their settings. In addition to that, I feel like it would be great to give us the ability to pick a Standard Voice while keeping its unique effects but also being able to transfer it to the Voicelab for additional effects of our choice. However, that won't be necessary if (even better) we have a "Unique Effect" panel or a more updated Voicelab that allows for such unique effects to be applied.
Favorite Examples on Voicemod V3:
-Odin (The bassy reverb)
-Fire Dragon (Literally everything lol)
-Crazy Clown (The ghost effects)
-Forge Covenant (The slightly delayed and distorted additional voice effect is just PERFECT. Also imagine what we can make with a bigger amount of additional voices the same way)