The Movie's pretty much exactly what you'd expect  Wonder Woman movie set in WWI to be: Steve crashes his plane on themyscria, Wonder Woman  Steals the sacred armor and weapons and stuff and goes to help him stop WWI, which she says Ares is behind. (Spoiler: she's kinda right)

The Good:
Nothing is especially stupid (except one thing I'll mention)
Costume design is good, EVEN ARES gets to wear his badass armour! (though his face isn't blacked out, but it's still there)
No one does anything blatantly out of their comic book character.
Action scenes are good, the last fight with Ares is really badass IMO.
The movie a does a decent job of showing how absolutely terrible WWI was, a war which, IMO is always overshadowed by WWII.

The Bad:
IMO there's just too much slow-motion in this film, like, yeah I get she can block bullets with her bracelets and that's cool and all but it wears on you after a while.
They kept the new 52 origin (though personally I don't take much issue with that)
They kind of portray Wonder Woman as kind of Trigger happy. (at least when she's a little kid, after that it's fine)
Also, minor nitpick, but Wonder Woman has an Israeli Accent as an Adult, but Greek as both a kid and an Teenager, which is just kind of silly. (IIRC, could be wrong)

If they do bring back Chris Pine (and look, I thought he had a great death scene and bringing the character back after that would invariably cheapen it, but on the other hand, more Chris Pine! it basically evens out!), I hope it's not like an identical relative situation, like a cousin who looks just like him, or a son or grandson, or nothing. That kinda thing always feels a little creepy!

has considerably more dialogue lines than the titular character?

Really good movie. The battle choreography was nuts (those flip hits and that fucking Tiger Knee from all the trailers), the combat scenes were really powerful with a serious sense of strength (smashing that tower like a bombshell), those skills largely made up for Gal Gadot being physically unimpressive, and there was no deal-breaking moment or ideal.
It's harder to fuck up a WW1 movie than something in the modern era just showing people being assholes, we know to represent the tragedies of war a lot better these days, so the emotional factor played out really well and was very effective, much less random than some Suicide Squad or BvS bullshit.
The cast diversity was nice, with a meaningful variety of figures, there wasn't any character in particular that got a horrible treatment. I've seen a few complaints over too few characters having more than 5 speaking lines, but I don't mind, I don't expect the focus to stray too far away from the actual central characters.
Humor was nearly non-existent, though, just a couple moments that walk up to your face and go "this is funny, please laugh here". Just don't see it for the jokes, but the rest was good.

Ares was a massive failure. Ares is the personification of war, as in bloodlust and rampage. I do appreciate and support the whole concept of "men have both good and bad, it's just up to them to chose through their own tragedy or just their own twisted mind", but this was way too much Loki-fied with the whispering and the snickering and the "it's not my fault, it's them, I'm just showing everyone how bad humans are". Also British Ares is vastly unimpressive. Just make his face a big mass of shadow with glowing red eyes once he transforms, please, the mustache in the horned helmet was just way too distracting. But hey, that was part of the whole "trickster god" image of Ares they went for, discarding any actual threat and pressure beside random lightning & telekinetic powers. He simply happens to have big powers. His "I'm the god of truth" line is fine if you understand that he believes war is the true face of humans (well, that's just what he thinks), but the "trickster god" curve on it was awful.
His plan to make the armistice just because "he knows they won't hold it" was only to hide the twist that Ares was the British guy and not the German, but it didn't make any sense. That twist fucked up his whole character.

I still like the Captain America (movie) image a lot more than the Wonder Woman (movie) image (I'm not saying that First Avenger was better, mind you). Cap is just someone who wants to do good, period, he'll save you and plow through whoever's standing in the way regardless of who you are and he'll never have doubts or give up, but Wondy starts doing good protecting the innocents but then she just stops when there's something she doesn't like and goes "maybe mommy was right, they don't deserve us". Fuck that, that's awful, don't judge a whole civilization like that, especially after you went all holier-than-thou yelling at people for not protecting the innocents calling them cowards. You don't get to do that when you change your mind so easily at the first thing you don't like, and disregarding the innocents that you saved 15 minutes ago. In that way, Trevor was better than Diana. I know it's the whole idea that she knows nothing of the harsh world and Trevor is already seasoned and has lived through actual war, he knows the good and the bad, and Diana has to learn that for herself, but fuck, she's no better than a weapon with no ideal. She's out of her isolated island for 5 days and already people don't "deserve" her. Well fuck off back to your island then.
Fortunately that was just for like 10 minutes and the final Trevor quick chat and her final conclusion ("in the end, just chose love") was much better, but she'll have to live it through in the sequel and pay back this "men don't deserve me" breakdown with interests and actual conviction. You want to be a hero, act like one.

It has flaws, it's not a perfect movie, but it's like any other movie - and that's a massive step up. This is an actual movie that is fine, not crippled with moronic, messy directing or writing with no sense or taste. It's something that you can actually watch and enjoy without turning your brain off just for the pretty fireworks.