Fifties retro sci-fi weapons *should* have dinky features like smoke rings on gauss rifles I reckon. You can justify it by saying it's a 'magnetic resonance ring' or some such technobabble, but in the end it's too nice an effect to waste!
Re: The"virtual dice roll"
They could mean a system where the player is rewarded for the accuracy of their aiming by achieving a "hit", but the character's skill determines how powerful that hit was in terms of damage, or whether it penetrates armour or has any special effects such as...