I loved the original Phantom Brave and have been looking forward to this!
I just finished the combat tutorial at the start and things are looking promising. It's the same style of combat as the original, with the turn order based on the Speed stat, circular radius for movement, and wire-mesh Area of Effect indicators for using Skills--very similar to its sibling-series Disgaea, but not as strictly locked to a gird.
It's running great on the Steam Deck. No noticeable performance issues thus far, though the combat tutorial and early cutscenes haven't been very busy just yet. There's a wide breadth of settings regarding resolution, post-processing, aspect ratio, and the mention of touchscreen support. Being excited to get into it, the only setting I've changed from the default at the moment is changing to Borderless Windowed to head off any potential mismatches relating to the Steam Deck's screensize.
Menus feel great and responsive, and the button prompts immediately picked up I wasn't using a keyboard and mouse after I pressed a button.
It's nice seeing Marona and Ash again; this picks ups six months after the plot of the first game.