Ok, first off, the minuses. The character design is very, very old school: 80’s, and the characters are pretty much expys from Galaxy Express 999, Harlock, Esmereldas, etc. Some of the plot points are a little too predictable, but the major reason I’m dinging it a grade is that the main characters are just a hair two-dimensional. Our zeitgeist has moved on, and we expect to see more than The Noisy Tsundere, The Impulsive Kid, The Drunk Doctor and so on. We want rounded characters, and this show doesn’t deliver that at all. It’s old-school, all the way. But what that means is, we get the good with the bad. It tells a dandy story, one that, so far, is hanging together nicely, rather than just flashing T&A in our faces and expecting us to not notice the dreck.

Why am I the captain? Because I have red hair, that's why. And I was the lover of the main character's older brother before he disappeared.
In episode one, which turns into a hunt and seek, this is kind of muted, but in the balls-to-the-wall battle during episode 4, it was just one twist after another as two brilliant commanders faced off. With one minor exception (ramming?), every single tactic was spot on, and the technology, given the adaptation, made sense. You see, while all this is happening in a desert, the conceit is that the “ships” have the capability to establish “Quantum fields” and travel underground through the sand. In short, although lasers and quantum fields and other buzzwords are flying, the template is WWII sub battles — hide and seek, sonar, torpedoes, etc. There’s a scene where Gido’s ship is chasing Binas’ through “reefs” (read, stone pillars beneath the sand), and she’s using sonar bounced off the various pillars to confuse Gido. My immediate thought was “Hmmm. if you could plot the timing of when each echo arrived, you could counter that trick.” Sure enough, Gido immediately orders his bridgebunnies (with which he is well endow- er, equipped) to use “doppler differential” to determine their actual location. And this kept happening — within the context of the contrived technology, the tactics made sense at every point, save the one I specified above (and I wouldn’t place any bets against subs ramming in desperate circumstances during WWII*). The result was a very tight, tense, and exciting battle that is that match of anything I’ve seen since the Battle of Aptic Gate in Battle of the Stars.
In short, definitely recommended despite the characters, unless you just can’t stand old school anime.
*Edit: This was not what I meant!
Well I just watched the finale.
There was a bit more handwavuim than earlier eps, but it worked for the most part.
It was VERY ’70s/early ’80s.
All in all I liked it for many of the same reasons you did.
Oh joy. we got a [spoiler]Greenpeace Victory again. Shades of Mars Daybreak.[/spoiler]
Well, It was not a nihilistic one.