It’s pretty clear that this is a DLC intended for experienced players. Gladius isn’t a game that’s forgiving of mistakes in general, and the Adeptus Mechanicus penalize misplays more than other factions. If you’re a Gladius veteran though, or at least have played a campaign with one or two of the starting factions, the Adeptus Mechanicus will make an exciting addition to your game.
Ultimately, Punk Wars stands out as a fun game with a rough-around-the-edges indie charm. It could do with some polish; some map and texture packs would be a welcome addition in the short term, and a fifth faction could drive interest further down the road. For right now, it’s definitely worth playing through at least one of the campaigns, especially at the low price point of $20 US. There is also a free demo available called Punk Wars: Prologue if you’d like to try it first. The full game is available for Windows and Mac on both Steam and GOG and, at the time of this writing, is 10% off on both platforms.