It's a channel setting, not a system setting. Some system types let you set an alert light if someone presses the emergency/man down button on their radio, but that has nothing to do with routine traffic.
One of the biggest improvements for the SDS100 vs. the BCD436 is the display. I can read it in my Tahoe, which I could not do on a bright day with the 436. But unleashing the color in the full database as Jon described would take things to another level.
I'm SURE it's overkill but the 1st thing I did after getting my shipping confirmation was order a 32GB card to go in my SDS 100 to match the one in my 436. I have different color patterns and alert flashes set for EVERY channel or object or whatever they are called on my PSR 800.
I would love to be able to customize every channel on the SDS 100 with custom background and text options too. I'm sure my 32GB card would be fine with that. Or at least have that option for different colors based on favorite lists or service types.