One question: On your third build, why do you not take the +5% damage to Salvos, on the left branch of the ranged combat tree? It would add to the RMB-attack, and you have spent points on that branch anyway.
The Boltgun is my favorite weapon, and I tend to use a mix of what you advise, mostly because I am too lazy to swap points around between single- and group-play.
Maybe I have missed it, but you could have stated at the start of the Video how many skill Points are needed for your builds...
May have to try this on the mid ranged Crusader (hate to admit it but I seem to like maxing the range with a needler when needed or Exitus rifle on the Assassin to match the distance with the enemies). Good job as always. Hopefully the 10% on kill is not a glitch and it is the description that is glitched so this build stays this way.