Flossy, I wouldn't be put off teaching German privately even though you didn't have the best experience teaching English in Germany. It does pay well and you'll be able to fit your hours around your parenting. You will find you're very grateful for that, no matter how annoying the students might be! You don't have anything to lose by giving it a go, since you can always go back to admin. And you could start while you still have a job and see which way you'd like to go.

I do know of a few companies who have job-sharing with their EAs. In fact, I think it's becoming more common to have a part-time EA or to job-share with the admin cutbacks a lot of corporates are going through. It might be hard to find, but possible.