These taste great with just squeeze a bit of lemon juice and Parmesan on top, but they are not the most visually appealing dish, so you may need to side with a favorite sauce or condiment (pro tip: spinach and artichoke dip is surprisingly great with it) to entice.
If you’re going to change out the vegetable, think about its water content compared to zucchini: spinach is a logical substitute, as its equally watery; broccoli is drier and may require some additional cheese to compensate. (Pro tip: separate out the meat mixture you intend to consume yourself, then add your preferred salt and spice to enable these ‘balls to punch above weight.)