i can’t believe i never commented on this thread.
i like when they come over the side a bit because they look a bit fuller after the frosting is on compared to cupcakes which only go up.
some believe that filling the baking cup more than 1/2 way leaves the cake with no support which causes it to flatten instead of dome.
another factor could be the temp of your oven. raising the temp 25 degrees might spur that quick rise which makes the cake dome.
good luck,
jen