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I use this in one of my orgs and it just works well.
No Names - that can be a feature if you don’t need it
Auto Rotation through the images
Drag and Drop by Cloud Analogy
https://appexchange.salesforce.com/appxListingDetail?listingId=a0N30000000q5DvEAI
I can’t even look, it looks terrible
Drag n Drop attachments with Dragger
https://appexchange.salesforce.com/appxListingDetail?listingId=a0N30000000q5DvEAI
It doesn’t look like lightning
Salesforce File Manager
https://appexchange.salesforce.com/appxListingDetail?listingId=a0N3A00000FR5UoUAL
I don’t want to even look.
Upload Guru
https://appexchange.salesforce.com/appxListingDetail?listingId=a0N30000000q6MkEAI
I refuse to look because it has vertical nav.