i build all mine 1 1/8 wide at the fades- tapering to 3/8 tips in a pyramid style, with the bend carrying through the handle.
handle 1" wide, by about 4 1/2 long. fades about 2" long each
a leather glue up on the handle area to add some bulk for the grip - but not so as to impede the bending- cork also works well.
this is just what i like for the ipe.
and as pearl says- as tough as the wood is, it does fret easily- so watch that your taper on the belly( tiller!!) is smooth and consistant.