My headcanon- Mr Makuro didn't think up the idea for HF right away, he went about trying to protect a city himself a la vigilante style, ninja swords and gadgets and all that (it's the guy's look. slap a sword in that hand and I wouldn't put it past him), then realizes one bot (or even a small team) can't defend everyone. Being a tech genius too, creates HF idea, years later, rolls out Heroes to perform the tasks he could only dream of.
Also hc- Meltdown used to work as a bio-hazard disposal worker, enthusiastic about his work. claws built to latch onto specialized canisters, tentacle designed initially to handle nuclear waste?
Eventually gets into accident working, neural net is messed up from said accident, and goes on rampage, eventually becoming what we saw in the show.
Gains 'Stewie Griffin' voice after accident