It looks like you have some good root growth just starting. Keep it in water for a time if you don't want it in soil. But it would do fine in either. New cuttings take most of their energy to develop new roots. Once the root system is established, new leaves will form. (This is pretty much true of most plants) Your Monstera will grow like a vine. I am sure you have seen your mom's plant. It will do well on a moss pole or trellis. When you decide to pot it up in soil, it would be a good time to place a support pole or trellis in with the plant at that time.