is it worth it with 4k turns all-x republic?

Yes, for the first 1/3 of the reset. Stop getting luck when you know you will stop exploring "1000 explore turns" later.

(That is, an investment in luck is only worth it if that investment is used for at least exploring another future 1000 turns.)

right on, I was thinking turns might help more atleast until like 10-12k acres