That’s how it is. VACE always renders sharp and detailed and yeah… you may say noisy (which could be blurred/smoothed in post with filters such as diffuse). FUN on the other hand renders smoother with a lot less details, but you may still render 720p with it (and it’s a lot faster). And all of the video render models suffer from occasional bug where pose armature might be composed over render.
Here is a 5 sec 720p mostly static video rendered with VACE FusionX following by 5 sec FUN render (no post).
I also did some compassion between VACE 1.3B and 14B here: [Official] 🎉 Welcome to AI Render Open Beta – Start Here! - #239 by 4u2ges