That's why the outer stem was invented. Not only does it look nice, it adds strength, impact resistance and most importantly, it covers the flaws.
The one kayak I used the overlapping method, I would run a strip long and use a back saw and cut the angle along side the oppossing hull shape. (the saw pressed against the opposite hull side) then the long or next strip runs over that end. Most people do it that way. If it comes out crummy, sand it off flat and fasten an outer stem. When it's all done, the overlapping joints are not really noticable anyhow and all that fitting work seems in vain.