Your notions all fine and dandy but we're talking real existing, legit devices here and not some random self-imposed challenges. Fact is, the ADS is a no-brainer that makes the other current existing scanners totally superfluous (unless there's actually a good reason for using them that I've missed). And no-brainers like this are always a strong indicator of a bad game design.
Cost was the reason.
The bad design, in this case, isn't so much the scanner (though I find it a bit simplistic) as the economy. Module prices don't increase, but rewards and money supply are run away trains.