If switching to oatmeal, go with the unflavored raw oats. It's not bad once a person gets used to it. Substituting milk with water is also perfectly fine.
Eating a low sugar breakfast does feel pretty healthy.
And if you can find them: I find steel cut oats (as opposed to rolled oats) way more enjoyable for texture.
As EZ-E says above, adding a dash of healthy fat (olive oil) above does improve the mouthfeel - as well as using a little more water than you need.
I much prefer the texture of porridge made in a pan on the stove to that made in the microwave. The stirring releases the starches from the oats.
I use rolled oats and cook with just salt and water which avoids the risk of the milk burning if you are inattentive, then add milk or yoghurt (and raw brown sugar) to my bowl.