If you scale everything,m simply nest the comp in a smaller comp and scale it once. If you enable continuous rasterization, it wil lretain a maximum level of quality (but keep in mind the otehr functionality associated with CR for 3D layers and passing through blending modes). Other than that you might consider the comp resizer script that comes with AE as wel las some similar ones you can find on sites like AEnhancers.com and AEScripts.com...
What are you doing: making the original comp smaller, or making it bigger?
To make it small, simply make a smaller comp, nest the larger original comp in the new comp, and scale the nested comp to fit the new comp.
To make it large, there's a script that comes with AE that can do the trick.
And I have absolutely NO notion why you can't get the necessary precision using the scale property as it is. I don't think I've ever heard that come up before. Your eyes must be a whole lot better than mine to see the difference between 23.42% and 23.43%.
Awesome! Didn't know you could put comps in comps. So if I put a comp within another comp, I'll only have the size the comp once (I think), that's great. As to not having to scale each element individually.
Didn't know you could put comps in comps.
You DIDN'T? You're not trying to use AE intuitively, are you?
I mean, you're beginning at the beginning, learning the basics, walking before you run, right?
You're not making the classic mistake of thinking to yourself, "Hey, how tough can it be to learn this stuff? I don't need no stinkin' basics!"