Eyes are going... I saw 'pop' gun, I knew it was one of the Lee's, Bruce or Brandon, luckily I only needed the last name. Bruce died early too did he not?
Louis XVI was the King of France, of a dynasty that had been reigning since the tenth century. Don't you think it was an extremely strong political act to decide to kill him? Furthermore, his wife would never have been executed if he had not been first. On the other hand, I admit that the execution of Marie Antoinette is indeed important, because it upset the Austrians.
Desperate times call for desperate measures. Given his options at the time, probably a good move. Imagine a situation where diving head first in hopes of breaking your neck is the choice of preference. That's a bad day.
He was last to go so he got a good view of what to expect from the first two who preceded. Fawkes had already been subject to some pretty heavy torture during his "interrogation" which King James I was actually personally involved in. You can check out the difference between his signature on his confession (top) and what was his normal signature (bottom). He hadn't been having a very good time.
My only memory of this comes from that Brad Pitt movie I only saw once, but I think I remember Robert Ford specifically was the one who pulled the trigger