"Aisha have you heard of automatic defenses?" *shows her the skulls "Aisha let me introduce to the automatic defense it attacks any intruder and adds their skull to the defense"
"And this here is The Cyberdoc. It's the one that cuts intruder's head from the rest of the body while implanting all that shiny cybernetics you see on table over there to make intruder into cyber skull. Oh, I probably should also mention the anti-insect measures. I don't have insects for one simple reason: they don't survive. When nobody authorized is inside, base pretty much is sealed and is not livable. I will leave the implementation to your imagination, but the moment I and Garment close the door from outside, if any intruding parahuman stays inside, they die."
Unlikely to be the way for Joe to go for. But no doubt will impress 13 year old girl.
He also has less frightening options, potentially something with potions.
And potentially a mastering ability in a form of food: give Aisha a taste and then start eating it without giving her any, because misbehaving girls don't get heavenly food.
What can he do to keep his stuff secret?
Punishment of Aisha aside (which I think is a futile discussion since Joe is not the type to go for most popular of listed options) Joe actually has a lot of ways to keep his stuff secret.
1. His flat is actually mostly 'disposable', nothing ties him down to the flat so it is easy to 'start anew' somewhere, preferably somewhere he can add defenses to (to know about strangers before opening workshop).
2. Joe was not investing enough into defenses, and this situation is a clear sign that it's time to multiply 'only a fool attacks tinker in his laboratory' by celestial forge.
3. Personal anti stranger measures are also clearly a necessity.
4. Between some alchemy and Cyberdoc Joe migh have some interesting options, like altering his appearance a bit. That can be useful if he decides that he needs to confuse public about his age, nationality e t c. Then revert everything with nanites. But this is a bit extreme...
5. Aisha didn't see much beyond what she already suspected: garment gloves plus entryway are not much of a leak. But Joe needs to figure out how much she knows.
P.S. Security measures.
Brian: Dragon Slayers somehow found and are attacking Apeiron's lab!
Alec: So? Apeiron will rough them up, gift wrap to the Dragon and be done with them.
Lisa: That won't happen, Apeiron is in Boston healing G-String Girl.
Alec: Shit. We need to leave the city before his lab levels it!
Boom! TSCHE-CHU-CHU-CHU-TSCHE
Lisa: Too late...
Brain: Was that a very loud transformation sequence?
Lisa: Just look out of the window... or turn on TV, it should already be on the news.
Alec: Damn... is that a flying robot building trying to squash a Dragon Suit?
Lisa: Fuck! Get down. It's launching missiles!
Alec: We are off course, why would.... fuck!
BoOm, BOOM, Boom, Bo-om...
Alec: You should have clarified that it was doing Macros Missile Hell, not launching missiles! That's two entirely different things!