Hi,
i will just give my advice with my brand new experience(so take it lightly and wait other confirm), you don't wanna transplant in a so big bucket if you don't want have overwatering problem, you should transplant them first in a 1 or 2L pot or so, they will grow much faster, in the coir all you want is get a big roots system as fast as possible to avoid any problem and to begin the multi feed(multi drip)
don't put any fabric at the bottom, there is no fallout with coco...only drain, and yu need to drain.
clay pebble at the bottom aren't needed but can help.
i will just give my advice with my brand new experience(so take it lightly and wait other confirm), you don't wanna transplant in a so big bucket if you don't want have overwatering problem, you should transplant them first in a 1 or 2L pot or so, they will grow much faster, in the coir all you want is get a big roots system as fast as possible to avoid any problem and to begin the multi feed(multi drip)
don't put any fabric at the bottom, there is no fallout with coco...only drain, and yu need to drain.
clay pebble at the bottom aren't needed but can help.