I have a composition of a keyboard with each key to light up on a note. I make the keyboard and several checkbox controls for the highlight. Now I put the keyboard composition as a layer in a composition that has all the note info.

Why can't I make the checkboxes inside the composition available to the layer so that I can have multiple note arrangements using the same keyboard composition? I can't make this link without hard-coding the composition name into the keyboard composition. So I have to make a duplicate keyboard for each composition I want to use it in.

It would be nice and efficient if I could toggle a button on these so when I drag keyboard comp into a new composition, it has the controls inside available on the layer instance.

ist not the first request of this kind, but i still miss folders in the comp/timeline window for more comfort. it not always make sense to have something in a pre comp – especially when its animated – and to jump back and forth to adjust keyframes. it would be so great to have it all in one comp and just pack layers into folders and giving them a mask too. the set mask option does not compensate the miss of folders with masks – just think of a photoshop without folders for big composition jobs – unthinkable today : )

a big comp with many layers in after effects could be clear and structured with folder and a time saver.

with the upgrade of the EXR workflow inside AE it is easyer than ever to do 3d compositing inside AE. But there is a lack of native tools to do so.
First of all the camera blur is slow, doesn't handle the aliased problems in the zdepth very well and doesn't produce a convincing photorealist blur...
Next the pixel motion blur was a great addition when it was promoted a few years ago but it would have been great to be able to feed it with a motion vector pass coming from the 3d render to be able to produce a nice motion blur.
There is no native relighting workflow inside AE you can't use your normal pass or your point position pass inside AE to do relighting or help merge your 3d passes and live footages.
For all those problems there are 3rd party solutions but all of the solutions 3rd parties came with are becoming old, are not well maintained and a bit clunky. And after effects and its users deserve better than those. We could use an other compositing package for those tasks but after effects have other capabilities that make it a for more flexible tool than its competitors

Enable Time Remapping doesn't seem to function properly when used with EXR sequences. I rendered a multi-pass EXR sequence from C4D and split it up using ProEXR from fnord. However, in order to save time, I only rendered the frames that had animation on them, figuring I could time remap it in AE to add handles to the beginning and end. Usually, the workflow is to move one frame back set a new key, delete the final time remap key and extend the ending layer. This doesn't work, everything afterwards just shows up black. As a workaround I've had to import stills and extend them to make the ending longer, which is a pain because it's a multi-pass render and there's several sequences. The reason why I believe this is an EXR related bug is because it seems to work fine with other sequences such as PNG and JPG. EXR is the industry standard compositing format, and AE is supposed to be an industry standard compositor. That said, it seems like it needs better EXR support.

The Set Channel effect does not seem to respect masks for the alpha source anymore, if the layer refers to itself.

When „Source Layer 4“ points to the same layer it is applied to, with the dropdown set to „Masks“, the effect would apply the layer’s alpha, but only within the layer’s masks. Now, it does not respect the masks at all and won’t apply the alpha.

Simple Setup: red shape layer with a mask, „Solid Composite“ with green color applied, then „Set Channels“ with „Source Layer 4“ set to the same shape layer, using „Masks“. See attached images for what the setup did before and what it is doing now.

The effect still seems to be working fine, as long as the alpha refers to another layer.

The issue might be related to the recent revision of the Set Channel effect with the may 2020 update: https://helpx.adobe.com/after-effects/using/whats-new/2020-1.html#Otherenhancements

I really would love to see the option to have hold key frames disable the rendering of motion blur. One example is that I have footage the has a time remap that ramps speed quickly from slow motion to sped up motion. I have masks that need to roto out a couple objects, but the motion blur jumps during the speed changes.this makes me split masks for the speed changes and adds a level of complexity to my comp.

Another example deals with a workflow that I use regularly that brings several similar shots into one comp so they can be comped together as one larger sequence. This helps with ensuring consistency between shots. This issue is the same though; between shots items like masks shift and blur due to the motion blur settings. There isn’t a way to turn off motion blur per frame as it’s global, so an option to use hold key frames and have them not calculate motion blur would be a great help.

Similar to workflows in DAW, I'd like to be able to parallel process effects on a layer. Simple things like being able to apply two seperate drop shadows that don't affect each other except when blending back together at the end of the chain. Currently 2 drop shadows in series would create a ghost of the other shadow. There are many more uses for this. The ideal solution of course would be a flowgraph/tree system but that's a lot of restructuring, maybe you could add to the "compositing options" a channel option so you can set them to multiple channels and then you can dropdown a list of channels and what blend mode to use and what opacity to use to mix them all back together.

As a side note, this would be great to add customizable order of operations - like alpha mattes being applied before a drop shadow instead of as a final step.