most people in eve multibox, in fact you could just ask in the mission running official forum... its rare for them to call it multibox, since most just "run multiple clients".
the easiest boxing setup is always missile ships, drakes are awesome. i used to do lvl5s making 300m/h+ and completely destroying any pirate stupid enough to try to gank me. (10 drake alpha is near 22k damage per T1 volley, 27k with faction ammo.) i stopped doing lvl5s since the next patch will nerf the drakes making them crap for lvl5s, but still godly for pvp. (you can do lvl5s, but you will need a logi) lvl5s can still be done with nighthawks or artycanes, if you have great skills.
also a step up from the drake you get into a Tengu, which is the king of carebearish pve, you can make easily 300m/h in CVA space with just 5 tengus running anoms, they have crappy anoms, but since the space is almost safe, and you'll be dishing out 4.6k+ DPS with T2 ham Tengus...
also add that in a good day you can even get a roleplayer to salvage after you that 300m goes to 350m, even after paying the salvagers cut. the one BIG problem will be ammo... it will be expensive. so going HML firing T1 missiles will be a good idea, even if your uber 300m/h will go down to 250ish
if you want to make money, i would go for drakes / tengus and spam lvl4s for practice then do anoms.
another option is doing lowsec exploration with a t1 cruiser fleet. you can clear sites really fast, and no one will engage you, atleast not other explorers.
lvl5 are always an option but you will need another "real" logistics pilot.
FW can easily make 60m/h per alt if you just farm it with each alt individually, if you want to box it, you can maybe make 30m/h per alt but you will have a ton of fun doing it. just follow the unwritten rule of eve pvp multiboxing.
DO NOT FIT POINT.
never, ever. ever. i mean it, not only other pilots will hate you, other boxers will hate you as well. its ok to fly 10 Slashers with ECM/webs/tracking disruptors/sensor damps/neuts and then /lol in local, but never point your target, its just not fair. either ransom, or just let them warp away once its clear they just been pwned. if they want to commit and they die trying to kill one of your alts good, but don't force the loss of their ship.
same goes for gate camps. no, parking 10 tornadoes 100km away from a gate is not ok. and i will personally go the there and kill em, don't care if we share militia and i take a standing hit

WHs can be somewhat fun to go into looking for fights, since c4+ have some really cool environmental effects that can make a fleet of assault frigates be as tough as a battleships

, but isk/h is crap, mainly because its not just pew pew, you will need to salvage. whoever if you apply to a WH corp and you make it clear that you are not just some dude "running many clients" and that you can actually apply a ton of dps, they will take you in. just don't expect having all your alts get a full cut of the profits.
for that, drakes are a good choice, arty munnins/lokis even better.
anyway, as far as ships/weapon systems goes, the only weapon system thats NOT boxing friendly is blasters, and given that rails still suck even after the buff i would stay away from hybrids, unless you plan on doing ganking or some other shenanigans. blasters suck due to the lack of manual flight control (you will have to rely on orbiting) and range limitations, your alts will often kill their own tracking by orbiting too close.
projectile weapons are completely retarded in PVP, because a boxing fleet has perfect volley timing. something a regular fleet, even veteran ones, kinda suck at. i would train artys to T2 mediums at least. sometimes, specially on Faction warfare, having a bizarre 650mm arty rupture fleet volleying logis from the back, can, and will turn the tide of the battle. (just yesterday broke a plex push with... arty rifters

)
autocannons are great as usual, and past the 5 alt mark, they will shred anything, be it tackled or not.
energy weaps behave just like projectile for boxing, meaning your "fleet doctrine" will be the same for pulse/acs or beam/arty
drones/sentries are VERY expensive sp wise but you can destroy almost all pve content with a fleet of gilas. just drop sentries and one shot anything smaller than a battleship, and two shoot battleships. small drones are really nasty on pvp, but a drone boat fleet is very vulnerable to smartbombs. (yet vexors are brawling monsters)
the one weapon system that makes boxing really OP are missiles, currently a fleet of talwars will completely obliterate anything in a FW plex, costing you less than 2m per ship (i fit everything t1). caracals/Bellicoses are as retardely OP as you can imagine. and drakes... well usually people run away the moment they spot them on dscan.
if you are opening 6 alt accounts, and you wont be buying any characters, then start with minnie alts, train t2 small projectile, tracking disruptors/jammers and some tank, then join the gallente or minnie millitia, while you finish training missile boats.
the gallente Militia will net you the most LP/h but until the ship rebalance updates the navy ships the gall store sucks. just make sure you buy as many ships as you can now, before they update them, and don't buy the ships, the BPCs are way better.
the minmatarr militia will net you less LP/h but the store is better. and ammar is fine, i would say its pretty much the same as the minnie side. both have space changing hands at every DT, so youll be moving around a lot.
the caldari militia has the best store, but it will pit you against the gall mill, we usually spend our eve time killing caldari FW farmers and taking their stuff
while you are in the militia, train missiles so you can go live in low/null. yes your standing will suck, and your alts wont be welcome in half the eve space, but who cares. you shouldn't be afraid of living in null with a boxing fleet, and lowsec faction police is a joke.
another option would be to train FW frig/dessie alts, then starting another 6 alts on the same accounts, this time training missile boats, artys, etc etc. in the backgound, while you play FW on the first set of alts with their training disabled.
don't train Battleships, unles you live under sov and you get called in CTAs, they are useless.
holy crap i made a wall of text. anyway, hope this helps ya.