I agree fully, I'm shocked that something of this nature got released and passed the expectations of the people connected with Cue.
To me it makes the system overall seem bad, and it ultimately seems that the overall goal is to allow voice dictation to control or select everything media based even though doing so makes usability or the index time suffer tremendously.
There is NO reason even in terms of CPU resources that the system needs to index every time at start up. How this is handled now just makes Cue seem slow, laggy, unusable, and overall kills the experience for the end user.
There is some form of memory or HDD space on Cue as it's used for time shifting radio broadcasts, and also tagging music from XM stations. I would certainly be willing to give up some time shifting space (still haven't even used the function) for a local index. Let alone all of the Nuance voice libraries, map data, Gracenote indexing, etc... are all stored on Cue somewhere.
There are many ways to accomplish this, GM if you're listening pick one!
It has been suggested (for SD/USB drives) to monitor these ports for a short time after powering down Cue or opening/closing the door. If the device that was plugged in wasn't removed once you've exited the vehicle then it hasn't changed! Leave the index the same and play music! This is merely 1 way of accomplishing this, and this way wouldn't require writing to the customers USB/SD card.
I will say this, and I mean it 100%!.. Other than a couple of unfortunate errors (power steering message, a charging/voltage problem, seat memory recall) Cue is the #1 problem with my ATS! It is the most frustrating part of the car and is seriously wrecking the overall great feel and drive-ability that the vehicle could be. It was marketed as revolutionary and had functions that I still to this day don't have (SMS being read to me, an App store, etc...) however even without the extra features the basic functionality is still flawed. Indexing is at the top of the list, followed by touch sensitivity and misplacement of touches vs on screen buttons (I'm told this is fixed), and still VERY laggy overall.
I really hope GM's listening because CUE is the #1 reason I wouldn't recommend the ATS to someone else, period!.