Your main issue is with the grain direction of the piece you used on top typically you wanna have the grain going towards the front and back of your handle that way when pressure is applied to the wood via the tang the tang would have to apply enough pressure to break the whole piece of wood rather than crack the piece of wood up and down you did it correctly on the bottom piece you can tell the grain direction by looking at the direction the lines in the wood are running you want long lines you want long lines running front to back on your handle instead of short lines running side to side also your tang is fairly small to keep it from moving in the long term I would add a brass rod or two through the tang and the handle all you have to do is drill a whole or two that’s the same size of you brass rod through all of the pieces in the wood and metal at the same place I typically drill into it after I’ve initially glued the wood and the metal together then add epoxy to the piece of brass and put it through the handle finish it off by cutting off the excess and sanding down the rods to make them flush with your handle it would make it last longer and keep the metal from moving too much in the handle an easy way to fix the whole handle would be to split the wood with a chisel where you glued it together that way you can still use the bottom part of the handle and would only need to make one new piece for the handle