E. if two arcanines breed will their child be strionger than Arcanine+Ditto? And if a ditto mates does that make it a purebred......WOw im going into this games schematics a little to much arent I....
No, it makes no difference which Pokemon your breed with, whether with Ditto or anything else.
The only thing is that different combos produce eggs at a different rate, but it doesn't affect the Pokemon that come from the eggs.