i think it has to be the new light xbow now? the crit range and the 3pc set bonus of +1 crit multi on 19-20. though you have to use that rune arm and the bracers. silent avenger set should probably be outfitted.

is echo trinket fixed yet? if not then improved deception has to come from guile or backstabber's. i dont know if i would use the ring slot for it as rings are too good in ddo atm with at least 3 named rings that could compete for the slot. nightfall, prowess, and commands.

the molten gloves save a feat and have armor piercing, while the neck slot is really weak for ranged builds, relegated to cannith or slavers unless using guile. there will be overlap on guile coming from ghostly on the cloak. baba goggles BiS.   

would start with these and fit in the rest.

silent set
armor
cloak
belt

renegade champion set
rune arm
light xbow
bracers

BiS
baba goggles
executioner's helm
ring of prowess
ring of nightfall


improved deception item :
guile

that leaves trinket, gloves and boots open to cover rest.