Hi Slade,
It may be a stupid suggestion, but why shouldn't the site manage the compression of the files to be uploaded, in cases where this operation is required.
Instead of members who, like MARCEAU, contribute to publish interesting orchestrations having, in addition, to impose themselves to compress their files (already scanning is a lot of work!!!), there could be a way for large files (separate publication or temporary deposit with then a compression made by someone else than the depositor or whatever...) to avoid discouraging interesting shares like those of MARCEAU. I guess this problem of files exceeding 25 MB must also happen with collections, etc.
In short, I think that someone who takes the trouble to digitize and share should not have to go through additional manipulations in order to share, in a simple way for him and for the users of the site, his interesting scores (because, here, we are talking about real scores and not of poor quality and of little interest as we unfortunately see them passing by). That's it! This is simply my humble opinion.