It's a likeable waste of time. If you watch it, you'll be doing well if you can remember more than one or two episodes of it afterwards. It's such a cut-and-paste of other, similar shows that even the characters themselves can't shut up about it, continually saying things like "this really is cliched" and telling the hero to be a "stereotypical leading man".
I did enjoy it, though, in a low-level way. It's almost empty, but it's good-natured. It's quite easy to watch just one more episode, even though it's mostly content-free. I disagree with the show's self-assessment, by the way. The problem isn't the cliches, although it's true that the show's clearly been stitched together Frankenstein-like from pieces of other anime. It's creakingly familiar. (Teenage boy hero forced to fight alongside lots of teenage girl warriors in magical battles where adults are useless, to save the world! He also has to sleep in the same room as his gorgeous, buxom partner!)
No, I think a bigger issue is the fact that the heroic characters have no meaningful characterisation. There are a few non-heroic characters around the edges of the show who are just about okay, though, if you look carefully. The heroes, though, are just... there. They're nice. It's pleasant spending time with them. However it's almost impossible to tell them apart, or indeed to care about putting in the necessary effort. Collectively they're a multi-headed blob of likeable. They're liable to grow some character traits when it's their turn to have a focus episode, but then they'll lose them again afterwards.
At its worst (ep.8), even the attempted focus episode fails because it's all so obviously grafted on and never feels convincingly set up in the first place. That episode's story feels like jigsaw pieces floating in a void, waiting for someone competent to join them up. That said, though, ep.8 also has a lovely little bit at the end when Everyone's Being Nice To The Chief. That's this show all over. It's a limp generic blob, but at least it's being nice about it.
Characters you might stand a chance of remembering include:
1. the hero's likeable little sister and embarrassing father. (Mum's dead.) Unfortunately they're stuck on the sidelines, only appearing when our hero goes off-duty and pops home for a bit.
2. Olga Breakchild, who has an awesome name but unfortunately sneers at everyone and looks down upon them. He's ostensibly one of the heroes. What's interesting about him is that he's also the lowest-status member of ALCA (Another Logic Counter Agency). He ranks somewhere around earthworms, although everyone's generous and supportive towards him anyway. He's the lowest of the low. He can't find a supernatural partner, you see, so he can't fight or go on missions. (His recruitment difficulties might have something to do with talking to everyone as if he's appending the word "scum" to every sentence.) He's a joke character, frankly, but the finale ends up taking him unexpectedly seriously, from ep.9 onwards.
3. Quetzalcoatl, a baddie who ends up getting recruited to be a heroine's partner. Admittedly he's also a cute critter and basically just comic relief, but at least you'll remember him. He's also styled after his Aztec namesake, albeit in a cartoonish way, which gives the show some refreshing design choices. (His partner will wear a garish Aztec-themed onesie.)
The show's set-up isn't weird enough to be interesting, but it's still odd. The aliens (or "foreigners") are supposedly gods and call themselves Athena, Venus, Valkyrie, Artemis, Nemesis, Lucifer, etc. (SPOILER: Lucifer's a baddie.) Supernatural power is driven on logic, which is effectively a synonym for "magic", and all the teenage girl warriors have to dress up as magical girls.
What does the story involve? Dunno. I've already forgotten. Does it matter? The girls fight random cartoonish entities, while Lucifer wanders around in the background being polite, urbane and respectful. If he's got business with the girls at ALCA, he won't send an army to knock down the doors. Instead he'll walk into reception and ask if he can have an appointment. (He's the anti-Olga, in other words, which adds something to their relationship in ep.9 onwards.)
I couldn't possibly recommend this series. Don't watch it. You'll be wasting your time. It has almost no points of interest and you could give yourself a hernia trying to find things to praise about it, beyond a very basic level of "quite nice as moving wallpaper" and "didn't make me turn off the TV". It's not good. That said, though, it's also avoiding the genre's worst traits. It's not offensive or sexist. It never turns into a harem show (except in the literal sense of "one boy and lots of girls"), because no one's got enough inner life to be romantically interested in anyone else. It's also not a Male Protagonist Ego-Stroke because the guy's so bland that he just dissolves into the soup of nice monster-fighters. He doesn't have enough screen presence to be anything more than another hero(ine).
Also, in fairness, ep.12 is quite interesting and promises to take the second season in a different direction. (Shockingly, there is a second season, but apparently it's also a fluffy schoolgirl spin-off with a different cast.) I've been rude about this show, but I watched it all and even enjoyed it. I'd probably watch a second season too.