THIS REVIEW CONTAINS SPOILERS
Note: Please keep in mind that a 5/10 equals average on my scale. Or in other words, overall I enjoyed this show but am unlikely to revisit it.
By this point the franchise has become tired and too formulaic. Usagi has failed to grow much over the course of the series, while her friends are forever stuck in a loop of fake development that never remotely pushes them forward. Characters who once endeared now frustrate and annoy. For instance, what does it matter if Minako tries to become a pop star, since this doesn't show us anything particularly new about her, nor will it be followed up on.
At this point even most of the supporting cast (Such as Naru) has been excised without ceremony. A major character (Mamoru) is even removed entirely because he serves no more purpose. New additions are added in attempt to spice things up, but only one of these, Seiya, feels like a fully realized character; and since we know his burgeoning romance with Usagi is destined to go nowhere, it's hard too feel much investment. His band mates only get a couple episodes of development at best and feel half-finished. Chibi-Chibi and Princess Kakyuu are nothing more than plot devices with at best one-note personalities hardly worth mentioning.
This season had an awesome premise with the idea of rogue Sailor Senshi, but this is wasted on comic-relief henchmen/monsters-of-the-day; and worst of all a main antagonist who turns out to be possessed, rendering her potentially intimidating personality meaningless. Like brainwashing this is a completely uninteresting motive for a major villain IMO; imagine how much more impact Galaxia could have if she willingly chose to go rogue? Ultimately she's robbed of agency in an 11th hour twist simply so we can have the typical happy ending.
Instead of even a halfway compelling attempt at drama, we watch her useless minions bungle about in unfunny scenarios for large chunks of the season, with only Lead Crow being remotely threatening. I've never been a fan of comic relief villains and missed the intense rivalry between the henchmen such as the Generals and the Witches 5. Furthermore, aside from a couple of Sailor Moon's brief moments with Tin Cat nothing is ever really made of them being corrupted Senshi, so the idea is entirely wasted. Say what you will about SuperS, but it was at least honest about its silly premise.
On the upside, there are some pretty funny comedy episodes (The cockroach scene is classic!), and in the last stretch things take a darker turn, for better or worse. Worse I'd say because once again Sailor Moon (The series) chooses to cop out at the climax, and when there are never any real consequences it's hard to feel much investment. Funny how easily Uranus and Neptune are forgiven despite their betrayal/cold-blooded murder of allies.
The score isn't bad and I noticed a couple pieces were recycled/reworked for Digimon Adventure. The new songs are catchy but overused. While the new opening doesn't quite match the original, it's a welcome change of pace.
As for my overall impression it's worth a watch, but I feel it does more to further diminish Sailor Moon as a brand than anything, failing to add anything substantial to the mythology. This series probably should have ended at S or possibly even R. (But then we would have missed out on the Outer Senshi.) Still, it's a passable entry.