It ruined the Horoscopes and turned them into MOTWs for the sake of "power levels," when that entire arc could and should have been done much better, had they not been so concerned with pumping them out one after the other to be the new MOTWs so Fourze could appear stronger.
I don't think your complaint there has to do with progression though. It just sounds like you wanted them to avoid the monster of the week structure that they kept up to the ending. They had to pump up weekly monsters anyway, and the Horoscopes suits weren't free. They couldn't have more Zodiarts AND all the Horoscopes we got.
How would replacing those Horoscopes with standard Zodiarts have improved anything? Even before the Horoscopes though, Fourze already had progression -like how the standard Zodiarts went from using "Last One" to "Beyond Last One", and there was also one with an unique evolution, before finally getting to the weekly Horoscopes. Fourze had a progression going on since the beginning, it didn't suddenly get a jump ahead just for the final form.
Who's to say the monsters don't just get stronger with the hero? Why does it even matter?
If you're going to make entire episodes about power ups, the power ups should actually be part of the story, otherwise the entire arc feels pointless. Again, just look at the Phoenix story. While it was going on, Phoenix vs Wizard was a great source of tension, but the other phantoms completely ignoring the progression that happened there just makes it all feel pointless now.
Maybe I'm just really burned by how badly Fourze did it - but look at W. It didn't suddenly introduce a new breed of Dopant for when Xtreme appeared.
W had already established the commander Dopants that were above standard W though. And they did introduce a commander that was defeated in two weeks after Xtreme's debut.
Still, Xtreme was relevant and important storywise even after its debut. W was consistently shown above Weather in power, which was a big change in the dynamics of the show. There was also the new Level 3 Nazca, and they soon also gave Xtreme power to one of the antagonists, and had W's abilities being limited as an actual plot point to make a battle against a standard monster of the week work.
They didn't replace the main class of monster of the week, but the writing clearly was considering the hero's progression (although they had to dumb it down a bit - Xtreme was initially described in magazines and official specs as having instant access to the Gaia library - and in the first few tv episodes with it, we get a scene where a light flashes on its head and Philip instantly shows knowledge of the enemy. When they introduced Claydoll Xtreme, they retconed it into just standard access at normal speed to make the story work).
Wizard has nothing like that. The hero's progression exists in a bubble almost completely separate from the story. It just makes entire segments of the show feel pointless. Wizard itself makes it even worse because Wizard's progression initially was a plot point and then it suddenly wasn't anymore.
I can get inconsistencies like that in crossover movies with multiple heroes and villains, but not in a solo tv show. It just makes the battles feel meaningless, and, in hindsight, also hurts the episodes that were mostly focused on those meaningless power ups.