If only your situation was the majority then it would dawn on the airline (i.e. won't be decided upon tomorrow) that letting kids preboard would be a good idea.
You statement makes no sense. The fact that many/most airlines have done away with pre-boarding for children would indicate that the PP's situation is NOT the majority.
Since most planes board from the front but have the rows at the back board first, there shouldn't be many people sitting in front of one's row when one boards (even if without pre-boarding), assuming one doesn't board at the end of their group. There will be some (frequent flyers, people with mobility issues, etc.) but there shouldn't be many.