Hey!
The idea here is when importing an After Effects project into your current one, you would have the option to either bring in the entire project, as is the current behaviour, OR to select the specific comp(s) you wanted to import and only they would be brought in, along with the assets used in those comps.
This could behave in a similar manner to Premiere importing another project - similar to the 'Import Project' modal. The equivalent option from that list to the proposed idea would be 'Import selected sequences'.
The reason this would be useful is to import assets from a different AE project at the moment can be time consuming. There are existing options - either import the entire reference project (which can either result in a bloated main project, or time spent pruning the unwanted parts, with the associated risk of accidentally deleting something that's used), or to reduce the source project and/or some variant of save comp as project.
Being able to select the comps to import would be a big workflow help, especially when working across multiple projects for the same client/brand. It would cut out a lot of steps, and increase confidence that you have a clean project and the assets you need are correctly imported.
I guess that expression-referenced objects might not come in properly, as per the existing warnings in Reduce project, so an info note would probably be needed as well.
Cheers!