exactly what devils own said.
i'd sort everything you have, sell off what you don't need, & stack as much as you can.
i always try to put as many resources as i can into commodity deed form, only because that makes them immensely lighter, although you can only store 60k of each resource on each commodity deed.
put the lightest stuff in each char's backpacks (125 items per pack, although leave enough room for the transfer token itself & your runebooks, etc.).
if you have the storage upgrade, you can put 150 of your heavier items in each char's bank box (125 items without storage increase).
i have never transferred with more than one packy, so i don't know if you can have more than 2, but that sounds about right, with stable slots and all. they don't need to be bonded, imo. just make sure when you land on your new shard, NOT to claim them from the transfer menu until you're safely inside your new house OR at your bank. i've lost MORE THAN ONE stupid packy on the walk between umbra bank and my umbra house, due to a vampire bat attacking and the stupid packie trying to kill it even when i yell all follow me and then dying and then i'm SCREWED and have to scramble to get all the stuff out of it's pack and into my house without people stealing it or the corpse decaying. didn't know until last year that you don't have to claim the pets right away, that you can claim them once you're inside your new house - duh to me! anyways, it's good to know.
depending on how much you have to move, i can't see how you wouldn't be able to move it all with 7 characters each with a full bank, full backpack and full packies...
good luck! and (you probably know) you can only transfer one char within each 24 hour period. a MAJOR PAIN when you're trying to transfer your entire account from one shard to another.