Romans we're not nice people and nether we're the Sanhedrin.. Feeding chistians too tigers and lions was mericiful in comparison.. Even Nero when he dipped christians into wax with a wick and burned them like candles (set on a pole) at his orgys was not as painful...
The price Jesus paid is all that more precious is the point of the movie.. Geese, you buy them books they eat the pages... or use the paper for other puposes..
The sword in the side was not to finish Jesus off, it was to ensure that He was dead. If He had cried out, the Romans would have, at that point, broken His legs. The liquid pouring out was also proof that Jesus had died.