Hello!
Unfortunately, I don't have the time to look through the detailed arithmetic you've provided, Islacrusez, but the general idea combined with ehlijen's suggestion reminds me a lot of my ideas on escort gunnery.
If one were to swap around the gunnery chart for escort weapons batteries (i.e. defences <=> ordnance, capital ships <=> escorts), I think it could represent the idea of batteries firing barrages of multiple, if smaller, weapons. Transports (etc.) would then be better at defending themselves against small raiders (as one might expect). As a corollary, escorts would need more dedicated weapons for tackling capital ships and defences (i.e. lances and torpedoes), kind of dividing them up into different role-classes based on weapons.
I think this swap would be a bit faster in both thinking time (once you'd become used to the system) and dice-rolling time (less re-rolls) than your idea... it would be interesting to compare damage output (unfortunately, I don't have time at the moment, but it's quite easy to work out).
(not intended to be advertisement for my own ideas
I just thought I could contribute
)
Although I have wondered about such re-rolling mechanisms... as long as there aren't armour modifiers, they are relatively linear in most circumstances (they can be a bit tricky if there are modifiers like in Epic: Armageddon, where Eldar lances were supposedly quite swingy with the same mechanic as in BFG).
Food for thought,
Thinking Stone
