I'm not sure what type of solution you are expecting. You probably know about cron jobs, but I wouldn't update systems in the blind as there are human interventions needed (and that is why they pay you to do this, right?)
If you had completely identical systems you might consider using something like rsync to bring in the differences, but figuring out which files not to rsync could be difficult, and I wouldn't do this while services are running. At least the update scripts are set up to manage restarting the services and merging in configuration file differences.
Perhaps if you explain what the problem is with doing apt-get commands we could see what you want to avoid.
If the problem is bandwidth and time to download, perhaps you should set up one box to act as your local Debian repository. There are Debian guides on how to do that.
Here are some tips on how to minimize the number of things you need to update.
When you install Debian, don't install Desktop unless you really need to use X on that console. Most servers do not need X installed. This can decrease the number of packages on the system significantly, and then you don't need to update as many packages.
Check that the sources.list is including only the repositories you really need. If you had experimented with some repository and forgot about that, you might be bringing in updates you don't need or want.
If you have run into trouble with blindly doing updates on a production server, be careful to consult the Debian upgrade guides when there is a major update (4.0 to 5.0). These will go through very well if you follow the upgrade instructions. It isn't as easy as running apt-get dist-upgrade and walking away. Sometimes in the instructions there are even pointers on when to run aptitude rather than apt-get - there are small differences in them.