Seems like it has good potential. Maybe a weird comparison but its giving me some Mount and Blade vibes. With the whole starting out very weak and slowly earning money to buy equipment to slowly become op.
Found a glitch where, if you select a part from the box, and then escape back to the previous menu, you lose the part forever. Lost the gun printer twice due to this. First time not knowing about the glitch, second time cause I instinctively hit escape to cancel placing it.
When choosing the internals section to install parts it. Is it necessary to have the "head, Torso, Arms, Legs" be buttons? Seems like you could just always show the buttons for the subsections instead. Would result in less clicking needed to navigate between body sections.
Finally, More just curiosity, not a suggestion or anything, but are you planning to add options to customize the cute anime girl, or keeping it locked to specific design? Custom waifus are always great, but I can also see the advantage of having a specific character design, especially when it comes to branding/marketing.
Cool game, cant wait to see you go with it!