Maybe you could improved Season 6 because despite that the series is alright except that there are some characters that never made sense or explained:
1.I still don't understand why Diaspro appear in Season 8 at Erakylon Palace instead still attending Erakylon Institute. But I have to be honest but Diaspro is a big disappointed in Season 6 who only appear in two episodes and then disappear for the rest of the season.
I really don't understand the point of this Diaspro being involved in "The Golden Auditorium" and "Vortex of Flames", I mean Diaspro team up with the Trix after they conqued Eraklyon Institute and I thought of the time that we get to see more of Diaspro in the entire season 6 but unfortunely that never really happen.
Because after Diaspro throw Bloom to the fire pit and then she suddenly disappeared after the confront with Bloom's sister Daphne and never been seen after this which doesn't really make sense. If she was serious about becoming the Trix's allied then we would have seem more of Diaspro at Cloud Tower along with Lazuli,Jade and Rhody and the rest of the Cloud Tower Elite.
2. In Season 6 Lazuli,Jade and Rhody were once Fairies from Eraklyon Institute before they decided to enrole at Cloud Tower and join the Trix as the Cloud Tower Elite. But after the Trix were locked away in the Legendarium book, Head Mistress Griffin return to take over the school again which leave me a big question like were Lazuli,Jade and Rhody were accepted into Cloud Tower at the end of the episode or have they given up and return to Eraklyon Institute to become fairies again like Selena? Because I would liked to know what becomes of them since they're never seen again as none of the reappear in Season 8 episode 16.
3. Roy appear back in Season 5 and return in Season 6 but I've notice during the whole series that Roy has been competing with Nex for Aisha's affection. In episode 15 he was ignored by Aisha as she and Nex share little bonding while surfing to the island. I can't believe the other Winx Club and Specialist haven't notice this situation because if they have then they would have done something about this.
What even more strange is that at end of episode 24 Roy hasn't appear in episodes 25 and 26 finale of Season 6 and never been seen again which doesn't make sense at all.
I would liked to fix the ending of Season 6 finale as Roy now knows that Aisha have feelings for Nex and decided to ending his rival by annoucing to everyone at Thorne and Daphne's wedding that he's leaving the group to return to Andros. That would make a better exit for Roy's final appearence in the series.