I grew up with the space program, and watched most of the Mercury, Gemini, and Apollo launches as a child or young teenager. It was all quite exciting, even given the reliability of those programs (Trivia: All of the Saturn V launches were not considered successes, despite reaching orbit.).
For those that care to remember or do the research, Apollo 12 experienced a lightning strike 6.5 seconds into the launch, with the electromagnetic pulse caused by the lightning resulted in the fuel cells going off-line (due to false overload sensing), resulting in the batteries being overloaded, which shut down most of the Command and Service Module, and this triggered just about every warning light in the craft. Fortunately, the first stage Instrument Unit ring remained functional, and kept the rocket flying in the desired attitude (else the thing may have went sideways and broken apart).
It seems that no one had anticipated that a rocket going up towards the clouds, with that long plume of hot, ionized gas behind it, would make for a very effective lightning discharge probe. Whoopsie. As a result of this, new rules were instituted which prevents any launch if there is lightning within a certain distance of the pad (20 miles?). Additionally, NASA installed an array of Field Mills around the launch site to monitor the atmospheric electric field potential, and, if the electric field is above a certain threshold, launches are prohibited.
Obviously, those won't prevent 100 percent of lightning strikes, but they have severely reduced the number of strikes. One can only hope that the metallic outer skin of the vehicle will adequately function as a Faraday Shield, and keep the lightning surge away from the interior components.
As for Jack Swigert, he was only acting on orders to stir the Oxygen tank. And, yes, there had been some stunts involving burping the pressure, but these were unrelated to the failure, for which the root cause was a redesign of the electrical system to a higher voltage system, without the corresponding change in the insulation on the wiring in the Oxygen tank, or a replacement of the thermostat. Coupled with this was the fact that the Oxygen tank was damaged in an accident, where it was dropped, which caused some of the plumbing to be damaged. In other words, there were a whole slew of problems, each of which was relatively minor, but, which when coupled, resulted in the disaster.
As for viewing launches, I got to see Discovery launched in April of 1985 (e.g., pre-Challenger), from a vantage point about 9 miles away from the pad. After the craft had launched, and disappeared behind a cloud bank, the sound finally reached me a good 45 seconds after the launch. And, although I say "sound", it was more of a vibration which shook the ground.
Regarding the timing/speed of the craft, I have to wonder if it wasn't already past the "Max Q" point with it traveling at 1 Km/second. Still, that doesn't mean that the Max Q couldn't have cause something to shake loose or metal fatigue to fracture something. I'm sure there'll be a thorough engineering analysis to identify the failure, and then to ensure that nothing like it happens again.
As for the range safety pyrotechnics, it certainly wouldn't be easy to press that button, even for an unmanned launch (I'm told that only commissioned Air Force officers are allowed to man the range safety button. I assume that's still true, even for private launches.). I have to wonder what the effects were on the officer that pressed the range safety button for Challenger. :-(
Note that there have been Range Safety commanded actions on a number of unmanned rocket flights.
As for the "low cost" supplier, I'm told that Alan Sheppard (who I was pleased to once meet) said that his thoughts, as he was laying in the couch in the Freedom 7 capsule being launched as the first manned Project Mercury launch, were "The fact that every part of this ship was built by the lowest bidder.".
As for using LEDs to grow plants, there's been considerable research into that (And, no, not just for "grow-ops"!). It seems that plants only need about two wavelength bands of light, and that the rest of the other wavelength bands are wasted. And, if I remember correctly, there has been some consideration of genetically engineering plants to use alternate wavelengths, although I don't know that too much actual experimentation with such genetically engineered plants has been done yet (or, at least, not published) (Then, again, plant genetic engineering is outside of my field of expertise, so I haven't played close attention to that field.).