I can’t find a good discussion/consensus about the order of cover art scans anwyhere - has this happened? e.g.
Put the front cover first, then the back cover second, then the booklet etc
vs
Put artwork in the order that they would appear when opening/unpacking a release
Perhaps it would be worth adding the resulting consensus to the guidelines.
I’ve uploaded 6000 odd scans of my CDs, and almost twice that from other sources. I was always taught the priority of MusicBrainz is identifying the product.
Front cover, Rear Cover, Mediums, Booklet (in page order).
That then gives the person trying to find their release the important differences first. When flipping between versions the real differences are usually in that rear cover and CD.
Variations kick in if there are boxes or slip cases. Then those come first, followed by the separate CDs in sub-sets.
“Put artwork in the order that they would appear when opening/unpacking a release”
This would not make sense to me as then the most important image ends up last. When you have a 30+page booklet that leads to a lot of scrolling. 
It also splits the rears from the mediums which are what you need to see together when playing “spot the difference”.
Following that logic, if you are doing an “unboxing video”, I would argue that when you pickup a CD you look at the front, then look at the tracklist on the rear, and then open it and see a CD before pulling out a booklet. 
I’ve been arranging things so that the medium is between the front and back of the item it is contained in. Works well for multi-medium releases like this one: Release “Trojan Rare Groove Box Set” by Various Artists - Cover Art - MusicBrainz
I usually do front > rear > booklet > medium. Something like this: https://musicbrainz.org/release/6a7ddb69-65d3-3a35-ac06-8d452b482620/cover-art.
Seeing this surprised me a bit, but I suppose it does work well for this type of release. I think it can be subjective depending on how the packaging is presented.
I generally do a top-down arrangement (Front, booklet, medium, tray, back cover, in the case of a CD/jewel case), but not for any particular reason, other than I saw someone recommend it some time ago. I seem to remember a conversation regarding top-down vs. “outside in” ordering, but I haven’t found it, and I don’t recall it coming to a decision.
[edit]
Ah, found it:
Thanks for finding that! I had a good search and couldn’t find it 
It’s still my preference, ~7 years later, to do it in the ‘top to bottom’ order.
The back cover is important, but this is a situation where I don’t find it helpful to have the database guess what I want - I would rather have the artwork arranged in a consistent way, and then I can handle the short scroll to the logical position.
‘Logical’ is of course open to individual interpretation, but for me it’s logical that ‘back’ is at the ‘back’.
I’m pretty much of the same mind. I wouldn’t mind seeing the guidelines make a call on this. I’d hope it goes the way I’ve been doing it, so I don’t have to re-order all the artwork in my collection. I’d much rather everyone else had to do it! 
I think this conversation confirms that the database needs a structure and relationships that are use to represent the packaging hierarchy in a structured way and not rely on guidelines and interpretations of those guidelines.
My general view of cover art order is “as long as you try to have the booklet in the correct order so it’s not weird, and the medium order goes 1-2-3-etc if you scan the mediums, it probably doesn’t matter too much”.
yes and it has worked well for many CDs in MB.
I’m not going to lose any sleep over what way it goes (I don’t think that the order is super important).
It’s more that when I see a back cover that’s not last, then I move it to the back, thinking that was the standard. Recently I have found out that it’s possible that other people are moving the back cover nearer the front when they see it at the back…
This seems like an easy opportunity to avoid more time wasting with a brief guideline paragraph.
The back cover is one of the most important images for making sense of which version you own. This is why I was always told it needs to be up front so you can make a decision on the version easier. Just the same as when you pick up the CD from your shelf. It is the second thing you look at after the front.
Burying it right at the end after all the stickers and trays makes it harder to flip through comparing multiple releases. Some pages can have 30 to 100 images on them when full booklets and boxes are scanned.
It splits up booklets (which the cover is a part of, for a CD), which never feels right. I really dislike how Discogs jumbles up everything to try be ‘helpful’…
Even in the most egregious examples of 100s of images it’s only a second to scroll to the bottom.
Usually this is true, though I have some CDs where the booklet is separate.
The other issue with the image of the booklet is that usually the image is of the first and last pages of the booklet, so a separate image is necessary for the front cover. In these situations, the problem of splitting up goes away. Ideally the first image of a booklet would the first page i.e. cover of the booklet and the last image would be the last page only.
When the cover image is also the first page
of the booklet, one solution would be to store the image twice. This has the advantage of keeping the order simple and not breaking up the booklet. It does incur the cost of
storing an extra image, but when the booklet has a large number of pages, this is a relatively small additional cost
But this is not a site for reading booklets. If there is a digipak this is not the case. Same with vinyl or CDs in slipcases. Putting a booklet first makes identifying different releases much harder.
That will be fun on a mobile. Even with only a four page booklet it will make identification really hard work.
Really? Hard work?
I don’t think prescribing some highly specific order of cover art files is a useful burden to place on editors (especially newcomers). Personally I tend to upload them in the order I get them from my file manager (which is usually the scanning order).
They are guidelines - nobody should be getting no votes because of cover art order!
I wouldn’t expect anyone to go back to change their old scans/uploads as a result of this.
It’s more to avoid pointless or back-and-forth editing.
With no broader interest for a guideline on this, I will apply the loose guide of ‘if I’ve uploaded it I’ll order it how I want, if someone else has uploaded it I’ll leave it’ in future.
If that also sounds annoyingly inconsistent to you, then feel free to bang your fist on the table and cry “a guideline please!”