Just putting my two pennies worth in here
Modern section equipment is very flexible depending on the threat situation, The lSW has not been withdrawn so it is still issued as a normal personal weapon 2 per section, I cant see this changing for quite some time due too money considerations, after all the LSW is nothing more than an a slightly heavier SA80 with a bipod. In Iraq were the armour threat is low the law is kept in the armoury and section firepower is boosted by either a gpmg or minimi depending on availability.
In SPMBT this could be shown by duplicating the modern section and changing at weapons for support mgs thus giving you a choice of sections depending on the scenario you are playing
regards Cus