I've left my geese to hatch their own, so wouldn't know about the overturning problems, but it doesn't sound like you've done that anyway.
With chickens, you need to check a variety of causes of wrong-end hatchings, including diet and genetics. Some hens simply don't form eggs right, and some fathers and mothers carry genes that cause deaths in shell or incorrect hatching due to congenital malpositioning. For instance (not sure if I've mixed up the left and right) chickens are supposed to approach hatching with their heads under one wing, left I think, and if it's under the other wing a lot of hatching failures result, and that's an inherited problem.
If you keep getting wrongly-hatched chicks and you're sure it's not your incubator-handling doing it, then you'd need to revise their diet or genetic lines. You may be running some breeders who aren't all they seem to promise. Best wishes.