Suggest opportunities for type size reduction by boxing enum content

I have a huge Rust project which is using a lot of RAM unnecessarily and there are no RAM profilers for Windows that show what the memory is used for, but I found out the huge RAM usage is because I have a lot of struct instances containing large fixed size arrays/vecs of Option<T> where T is potentially huge (because it itself contains fixed size arrays and other such types etc.).
It would be very useful to be able to find out opportunities for type size reduction by boxing, e.g. changing a struct member from Vec<Option<Huge>> to Vec<Option<box Huge>>.
Could this kind of suggestion be added to clippy? :)
So that it's easier to track down all such instances of this situation..
It should be able to detect this for other enums than Option as well.

In addition to that, it would be nice if there was a way to output a list of the largest types (structs/enums) in a crate, descending by size, to get an overview..

No files, tests, or entry points are named. Start by narrowing the request to either enum-boxing suggestions or largest-type reporting, then define the expected output and tests for the selected feature.