Would that mean I am borderline on the level that employment guidelines allow in your system when the line does not show up as good as the control line?
No it wouldnt. To conclude that youre borderline on the basis of line intensity would be speculating (and wrongly so) since assays lack the ability to yield a quantitative value (unlike the GC/MS).
There is no meaning attributed to the intensity of a line. Even synthetic urine controls (which contain no drug metabolites at all) can produce a faint line on an assay. Its still a negative.