I liked your article, I agree with most things but I would like to emphasize that the drawings or animations we always see of the space junk are taken out of proportions. The space junk is so small and sparsely distributed that engineers can calculate many trajectories which wouldn't intersect with any of the known tracked objects by distances of kilometers. Sure that it would be a problem in the future if we keep dumping everything in space but for now we are in no need to panic.
As for asteroid mitigation, you could write an article solely on that. :P There are newer studies that explore a lot of other possibilities.

Cheers!