It may not be the patty pans or the packet mix, but your oven.

90% of ovens have hot spots that make baked items rise inelegantly!

My advice would be to use the same packet mix you are using, and use an electric handbeater for more time than the packet suggests, with a about a tablespoon of extra milk. Only half fill the patty cases.

If they do rise wonky, just slice to tops off and ice them flat, or make butterfly cakes!