I dislike the idea of having to analyze each icon individually to determine what it is, because that just leads to the mosh pit defense.
Say someone hacks into my commlink. I say that I sculpted my node such that it has 1,000,000 icons, which I, as the creator, can instantly separate as wheat and chaff based on access #s I have memorized. The intruder, however, needs to roll potentially 1,000,000 analyze tests to find whatever he's looking for. That's really ugly.
I prefer to play where an analyze test is done on the whole node, showing where various systems are located, and any stealthed icons get to roll opposed with +2 (or against the original roll -2) to represent the searcher being distracted by cataloging the rest of the node.
There are plenty of places where Matrix RAW is borked, and matrix perception is one of them.