...Cloud backups, on the other hand, are for disaster recovery....It really doesn't matter how long it takes for the initial upload to the cloud, that period of time is irrelevant. It will be what it will be, and it won't adversely effect your up/down speeds for whatever else you're doing...
Cloud backups are OK if you have a little bit of data, or don't mind picking through your data and pulling out the important part, and don't have an ISP with a data cap, and if you don't mind a very long wait for both backup and recovery (possibly weeks).
However it's often much faster and more effective to just backup everything to a portable hard drive, walk to your mailbox and mail it off site, or just put it in an on-site fire/flood proof safe.
It doesn't take much activity to accumulate a lot of data. I have shot 50 gigabytes of raw stills in one day, and that wasn't trying hard. It very rapidly becomes infeasible for cloud backup.