It's pretty charming but not worth what they charge for it. 2 and 3 are asset flips with a little new content.
Gameplay is passable, they never get very hard but it's not an autobattler either. Main issue is repetition, especially in 2. Despite having a decent core it doesn't go far with it.
Character-plot interfacing suffers because someone can die in every chapter, main events get written very neutrally so they can proceed no matter state your team is in. Most of their characterization is exclusive to intermission events between pairs, which requires multiple playthroughs to view all of them.
I liked the story itself, but some people find it divisive because the tone shifts dramatically in 2 and 3. 1 reads more like a grounded, gritty war story, while 2 and 3 have rapidly escalating stakes, technology, and a few asspulls.
I'd give 1 a pirate and see what you think, it's not that long.