I use arq as well. Some things I don't like about it are:

1. There's no information about what it is doing (which file are currently being backing up, what's the current upload rate, what's the estimated completion time, how much data is left, etc)

2. Large files (like VM images, or crypto containers) block small files from being backed up. Essentially, your backup frequency can be no more than largest_file/upload_rate (well, it's more complicated than that because of deduplication)