I don't think a more modern band would have worked for the storyline. The original idea was for Sookie, Lorelai, and Rory to go. Madeline, Louise, and Paris were a last minute addition when they were studying with Rory. Lorelai was trying to foster a tenuous relationship into something friendlier.
It always impressed me who ASP could get to appear on the show. I don't remember the name of the band that appeared on Girls in Bikinis', Boys Doing the Twist - had never heard of them, never occurred to me they were a real life band until I saw them on Austin City Limits.