Star Trek (1966) - 7 questions

Question: How in the world did Hikaru Sulu, whom under all circumstances is Japanese, end up with that last name? Even in the novelization of the Star Trek IV, he meets his great (great.) grandfather named Akira Sulu. (Question is aimed more for a production explanation than a story-based one.)

Answer: Production explanation: Gene Roddenberry took the name Hikaru from the legendary Japanese novel "Tale of Genji" and Sulu from the Sulu Sea, located in Southeast Asia. Roddenberry wanted a universal-Asian name and said, "[Since] the waters of a sea touch all shores," the name Sulu was perfect. Story-based explanation: presumably somewhere in Sulu's family line there was a non-Japanese (probably Filipino) male whose surname was passed on.

Question: What was the fate of all five series' captains?

Answer: According to on-screen text visible in one episode, Jonathan Archer served as Chief of Staff at Starfleet Command, then was appointed Federation ambassador to Andoria. He then served on the Federation Council, before finally holding the office of Federation President for eight years. According to additional biographical text that ultimately never appeared on-screen (and therefore may not be canon), Archer died peacefully at home in 2245, the day after attending the launch ceremony of the Enterprise NCC-1701. James T. Kirk died on Veridian III in 2371, 78 years after he was believed killed on the Enterprise-B, as seen in Star Trek: Generations (although novels written by William Shatner have resurrected the character for further adventures, these are of uncertain canonicity at best). Jean-Luc Picard remains in command of the Enterprise-E; while a future version has been seen as an ex-Federation Ambassador suffering from the lethal irumodic syndrome, this remains only a possible future. Benjamin Sisko was taken into the Celestial Temple by the Bajoran Prophets; a series of follow-up books reveals that he eventually returns and lives on Bajor with his family, but, as with Kirk, the canonicity of these novels remains unclear. Kathryn Janeway was promoted to Vice Admiral upon Voyager's return from the Delta Quadrant and, when last seen, held a position at Starfleet Command.

Question: Why don't any of the Treks to come use any of the useful things that Enterprise discovers? A psychotricorder can record your memories! Scalosian water speeds up humanoids to the point they can dodge energy beams! A veinful of kironide makes you a powerful telekinetic a few minutes after injection! If Picard, Sisko and Janeway had just read Kirk's logs, the Borg and Dominion wouldn't have had a chance.

Answer: They do use much of the technology, just not the particular items you mention. There are many reasons: perhaps the technology was deemed too dangerous and outlawed (as with the planet Talos), or found impossible to reproduce. The Prime Directive would prohibit them from stealing the technology too, no matter how valuable.