Just catching up with this project and it looks like solid progress.
The maser beam looks cool, the first thing that came to mind was the thunderbolt from Quake 1, if you have not used that gun I can highly recommend it - super satisfying and great audio too. I have seen those laser beam tanks in Godzilla movies but always thought it was lame they never did any damage from what I remember.
Also for the art, I love how the intro cutscene shot looks with the 80s retro futuristic look. As for your promo shot that does also look nice but hopefully the game won't go that far into a sort of "anime direction" if that makes any sense. Seeing people in more casual outfits in the hangar/workshop area is a cool touch though (think that was mentioned in the last dev blog), but I think games that constantly overlay screens with faces whenever a voice it talking over the gameplay can get distracting.
There is probably a good middle ground that lines up with your vision.