I am a pastry chef from Le Cordon Bleu. I bake a lot but a common cupcake issue for the casual baker is overfilling the cups. This causes overflow. The current design does not have a solution for the overflow. It also appears that the cups are to close together which may cause the cupcakes to bake together. I have a few suggestions. Instead of each tin having one connection point on each side, what if each side had a 1/2 to 3/4 in lip forming a square around the circle. the right side could have a hole the left side could have a connection point to fit within the whole of the contiguous tin. Also, a fill line within and outside the tin to prevent overflow. Inside if no liner is being used. Outside if a liner is being used. I will post a sketch

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