Maybe starting with cutting down on the amount of sugar you put into whatever it is you bake?

Banana sounds good, maybe raspberries (but not with white chocolate, as that is pretty much just sugar), apple and cinnamon... Apple and raspberry. Other berries... If you use frozen berries from the supermarket, they are pretty good quality; use them while they are still frozen (all broken up) and the colour won't go through the muffin/cupcake batter. Or muesli...

Savoury muffins/cupcakes/slices; finely chopped sun dried tomatoes, ham or bacon, cheese, mild mustard, spinach, pesto, dill....

Here is a list of baked goodies I have in couple of 'healthy cooking for lunchboxes and kids' which may give you some ideas, or if you want me to post some recipes: ABC muffins (Apple, Banana, Chocolate), Blueberry bran muffins, Spiced fruity muffins, Double chocolate and banana muffins, cheese muffins, pikelets, boiled fruit loaf, apricot balls, anzac biscuits, gingernuts, choc chip cookies, zucchini chocolate cake, apple cake, pineapple carrot cake, popcorn, rock cakes, orange and coconut cookies, etc.

Hope this helps.