>>2962959>Tadashi died when he was killedSeriously though, I have this headcanon that Tadashi rushing into the burning building wasn't the first time he did something like that. Basically Tadashi felt a lot of... something when his parents died and basically developed Emiya Shirou Martyr syndrome and kept trying to save everyone until something helped him snap out of it enough to build a robot that could save everyone. So basically, Baymax was always meant to be superhero-duty capable, Tadashi just wanted him ready for medical first.
>>2958338I really wanted to see Hiro don Yokai's mask and start using the microbots himself (even enveloping him a bit) until he's got Yokai cornered and someone makes him see his reflection, the cloak of microbots and the mask making Hiro look like the spitting image of Yokai.
>>2964609I'd like to think Callaghan didn't actually start the fire (who did or if it was just an accident is another story), it helps close a plot hole with the professor seeing an opening and taking it.
It also puts in a few more parallels to Krei where both theoretically could have done something (Callaghan just saving himself under his own power or Krei calling off the experiment) but ultimately chose to go through anyway because they though the risks were within acceptable perimeters.