The LSW is ment to go to the most compitant rifle man in the section, due to the higher rate of fire supplied by it, 30 rounds per min normal rate of fire compaired to 10 for the rifle, and 60 rounds per min for rapid compaired to 30 for the rifle.
As for the GPMG god knows ours are all attatched to our Spartans and 43's.
The rest of the weapons in your list for us Engineers are issued on deployment dependant on the role we are doing...
We had minimi out on Telic 5 when i was with Recce Troop in 21.