Translation of tiefgreifend

I hope you you had a successful week in Dortmund. Because of the bad weather at the last moment I could not get on my flight to Dusseldorf and I have stayed home. I was afraid to fly.
The fact that I have received many emails from students in order to make Vocabulix known is a personal success for me. But I think that a new website with many pages would be better for future uses.
I would be glad if you can tell me more about the United States, of course in German! Maybe we can talk again when you're back at home, what do you think? That would be a good practice, wouldn't it.