It's really hard to define what a thought is. It's like asking what a "color" is. You can show some colors or just give some technical gibberish like different electro-magnetic wavelengths getting interpreted by the brain etc.

They are more like simultaneous threads.

Nope. No 2 thought instances exist simultaneously in a single mind. The rapid succession might give us the illusion of multi tasking. But only one happens at a time.

Flying insects for example operate at the time scale of milliseconds.

This is part of the evolution. I do think humans can achieve this level or even higher levels of sensitivity through training. Take martial art for an example.

Thanks for your thoughts :-)