For the second handle I had run out of long enough pieces of lilac* - they had already been cut to lengths suitable for the fireplaces. I stuck to the zero budget way and went for some short just long enough surplus wooden planks of spruce with nice uniform fibre direction. I heard somewhere a long time ago (as a child in fact), that to make the bow strong of certain ships, the wooden planks were cracked into shape along the fibres (sounds difficult for long planks though). Well since I have no lathe and the spruce wood is low density, but yet the handle should be strong/stiff enough - why not give the method a try?
If would find that there would be an advantage with curved handles I should consider all curved pieces of wood from the garden as potential handle material and not just something to be used for heating. Usually when a branch is curved I put the cut in the middle of the curve, so that I get two semi straight logs from it to fit into the pile of logs.
*Of course I could go and cut some new branches from the bushes (there is plenty of it), but I'm in a several year process of rejuvenate the bushes and do not want to deviate from this. Not until the flowering period has passed you should do the cutting. The first year you do the central parts of the bushes, later years you work your way more outwards and during the third and fourth year you work at the "surface" of the bush.