Even with 5 people on board you are going to have a nightmare trying to get the lines cleared fishing 7 lines for Hooters! 5 max
i can see where that me be a problem for a less exerienced captain and crew or a smaller boat but not for me........ 7 to 9 lines out when i'm trolling (and that doesn't include teasers)........... only when i'm fishing strictly for blue marlin or 'hi-speed' trolling for wahoo would i consider trolling with as few as 5 lines out
where i'm at we don't have any 'wahoo only' waters or wahoo tourneys that would justify a 'wahoo only' spread except for hi-speed trolling and for most hi-speed trolling you wouldn't be dragging diving lures like yozuri bonitos*
if i drug a few diving baits in my usual spread i could troll up to 11 or 13 lines at a time w/out a problem but when i troll alotta lines out it's usally because i'm offering up a smorgasbord of lures to attract a variety of species from marlin and wahoo down to bf and dorado
if i'm into a good wahoo bite, i might go with as many as 5 wahoo lines in the water but will keep the other lines varied cuz i know there's always other fish around or the wahoo wouldn't be there
*here's a lure i wanna try for hi-speed wahooing........
http://images.cabelas.com/is/image/cabelas/s7_122846_007_01?$main-Medium$
they claim this 8 1/8", 8-oz, lure is engineered to run true and can be trolled at speeds exceeding 20 mph (i wonder how that might work for some o'you popper fans casting with high speed spinning reels around rigs and ripping it outta there for a hoo bite,........ hmmmm

)
anyway, you just don't catch the big wahoo (60#+) by hooking up with 4 or 5 at a time even if you think 'they' run in packs too........ one thing nice about big hoo is they're gonna fight deep and straight to the boat as-long-as you keep it in gear........ all you gotta do is clear just a few rods where you wanna boat the fish and even then you should only have to bring in those lines a little shorter than the others to avoid tangles but most everything can be left out............ 60# hoo're gonna be about 5' long and i got 11' of transom to deal with'em....... one person can stand in one corner and gaff'im in the head and the other can stand across in the other corner and gaff'im in the tail and just swing'im aboard between each other (been there/done that)
if all i'm catching is a buncha dink wahoo that're only running about 4' long, bring'em on!....... the more-the-merrier............ but i ain't gonna go down to just 5 rods just because o'that