I've played with a lot of low output ceramic pickups too, thanks to my experiences with Epiphone. I wouldn't call them brighter - just different. Under high gain they have a more grainy sound which is more metal, while alnico magnets are less modern and more smooth. Ceramic pickups have a more fuzzy top end which kind of flattens out, while the treble of alnico pickups is the opposite of fuzzy, whatever that is. It's hard to describe what I hear, especially since I'm probably just imagining it anyway.