The series started strong and ended strong, but had a weaker middle
Having re-watched the entire series over the past few weeks (first the complete, superior Rhino set, and then making up the balance with the Shout discs for the episodes that Rhino never covered), I have to say that the series both started strong and ended strong, but had a weaker middle section.
The opening arc remains by far the most compelling storyline, right up to the battle of the bands, with the culminating "Music Is Magic" video, and the girls earning the right to live in the mansion.
Then, the series slowly began to weaken, with less interesting episodes. The new Hologram, Raya, added nothing (although Jetta turned out to be a great Misfit).
But toward the end, once the Stingers were introduced, the series really picked up again. Riot and his girls were each quite intriguing characters, especially Riot himself. The presence of Riot revived the romance angle involving Rio which had been such a source of story energy in the early episodes but had faded into complacency over the course of the series.
Even other episodes toward the end, such as the "Beauty and the Beast" show (which uncannily anticipated the Disney movie in a number of ways), were quite strong. But the Jem-Riot-Rio-Jerrica love quadrangle was fascinating. Jem was loyal to Rio, but she did have a genuine attraction to Riot.
Such a pity that the series didn't continue. I always enjoyed it, but reviewing it now, it's even better than I remember.