Adjustment layers. How many effects?

One thing to note ... on an Adjustment Layer, if you mix 8 bit effects with color correction (which is normally floating point) or other high-bit effects, the whole layer may get processed in 8 bit.

If you use any 8 bit effects (ones without 32 bit ago block in Effects panel) put them on their own layer.

Neil

The gpu cannot handle endless effects. If there are too many the render bar will turn red.

I don't believe there is. However, it's up to you and how you build your workflow.

Usually I have 3 adjustment layers: one for color correction, one for color grading and one for effects.

Some effects are applied directly on the file like noise reduction and warp stabilizer.

Some times I nest a file with it's adjustment layer, especially when there is masking and compositing involved.

As Neat video noise reduction needs a 'noise sample' I find it better to add to the individual clips, assuming you have more than on clip in the time line.