This is basically a second generation computer, whose heyday was in the first half of the 1960s – after vacuum tubes, but before the first integrated circuits.

It makes me wonder, what transistor family would give you the best performance for this (very unusual nowadays) use case? Obviously not MOSFETs.

From what I understand, germanium transistors were most common for 2nd generation computers, because (at the time) silicon transistor technology wasn't sufficiently mature to be used for that application.