When I send my v19 file to my accountant, I zip the file. That means the 157mb file becomes a 25~mb zipped file.
Why not use the same concept when you first require users to upload the AR Live ...
With the latest live version you can just invite your accountant to access your live file. No longer do you need to send the file to them.
Once the initial upload is done it is much faster following times (if you take the file offline for example).