Headscratchers / Star Trek S2 E20 "Return to Tomorrow"

• Numerous fans pointed out at the time that the Andromedan androids on Planet Mudd or Korby's planet would have worked out great for these guys. The episode would have been a lot different, but could have been very interesting. Unfortunately there were rules in place about continuity, so this couldn't have been used even if Roddenberry/Coon/Justman/etc. had thought of it.
• Why didn't they just build robot bodies instead of going into receptacles for 500,000 years?
  • Also, why are they so convinced that robot bodies won't ever have the sensory capacities of living ones, if not better ones?
    • Or that they themselves would be capable of inventing said improved robots, and why didn't they have them already if they were so advanced?
    • Out of universe, I think this is just how robots were thought of at the time. In universe (and remember this is a somewhat mystical universe where living people are special things that can have psychic powers, have their disembodied souls transferred around, and evolve into reality warping energy beings), I imagine there is just something about the experience and “feel” of inhabiting a real organic body that is just different from a hyper-advanced robot body, even when the latter technically has all the same sensory powers as the former. And at least for Sargon’s race, the former is far preferable to the latter.