I see DO's weekly backup as a convenience feature for if you need to restore your server, not as your primary backup method. Use the DO snapshot to restore most of the way, then run an up-to-date differential restore from your other (real) backup solution (that is hosted somewhere else).
But wouldn't it be much more convenient (largely because of the complexity) to have the complete backup solution at the same place (i.e. DO)?
Obviously, you want some offsite backups rather than completely relying on DO but that should be for disaster recovery (massive failures in DO's DCs, etc) rather than a more routine one.
