How to keep the details and line thickness in freestyle (camera movement)?

I’m trying to do a project with freestyle cartoon style.
I have two characters, one large and one small, both quite detailed.
When I render separately I have no problem, but when I put the two together the small loses much of its details. Freestyle lines become too thick to the model and lose a lot of detail.
The problem, I think, is bring in / out the camera to frame the two characters in the picture.

Is there any way around this?