It just seems silly to have a tech nerd on the team, yet never have them do tech stuff.
I wish she had built herself new limb enhancers. Yes, her ultimate arc was about developing as her own person free of Homeworld's impossible standards, but if anything, a new set of enhancers she built herself and controlled with her magnet powers would've been some nice symbolism. Also, the limb enhancers are cool, dammit.
Oh, and the hypothetical new enhancers wouldn't make her taller. Peri would still be a shorty.