hmm... no, no flare necessary unless u want one, flash hiders and muzzle breaks are common, but not really required. As for the Jetpack, most ppl who use 'em have some sort of strap system that they hide under the plates. One that I've seen a lot is a mil-spec rucksack frame worn so that once the plates and jetpack are on, it is hidden. I would suggest you do what's comfortable for you. If your jetpack is light enough in weight, you could theoretically attach it directly to the backplate. Commander Cody wears a compact jetpack on his armor that attaches directly to the back plate, and most ARC troopers, RC's and the specialized Airborne troopers had backplates made to accept their jetpacks. Hope that helps.