I defined 3 Custom tags
Box Set (name)
Disc (name)
Disc Volume ( things like the Beethoven edition where there are smaller Box volumes)
Then create a view where box set is not Empty,
To achieve what you want on this setup would be as English Tiger says , individual Album name becomes Disc Name then rename the Album to the box set name. So that would appear as one (big) album.
Take for example the Brendel Philips box , this works well. If you make the Box Set tag multi value, you can split a big box into smaller boxes while keeping the big box as well, eg split off the Haydn sonatas 4 cd box etc
I keep the artwork specific to the Album/Disc where it’s appropriate
One thing that’s missing in MC is the ability to apply an overall box set folder and Maintain the individual artwork. In this example you will get a “fan” of the artwork . It’s a feature request that would require a box set to be a distinct object ?
If you want some clarification then PM me , happy to share images