The constraints are kind of ridiculous and hugely unfair.
They first put strongest teams in a group (which is immaterial whether your group will be named A or F), and from then on due to the constraints the whole thing is built on several 'fixing by elimination' which creates unbalanced groups.
Why can't they draw the fucking groups with the only constraint being teams from the same country not being able to play each other, and after everything is done they will determine group number and TV constraints will be factored in there.