Within a certain range, the height of your tank on your back is a matter of personal choice. The higher the tank is on your body, the more the weight of the tank helps you get horizontal. The price of this trim advantage is the potential for impinging your neck/head on the tank valve and regulator. It sounds like you would be happier with a lower tank. There's nothing wrong with making that choice.
Regarding the great trim controversy. It's important to remember that you're engaged in recreational diving. You're under no constraints regarding other people's idea of how you should be oriented in the water. If you're more comfortable with a slight tilt and aren't covering a lot of ground, it's nobody's business if you enjoy a leisurely dive at a slightly less efficient angle. As long as it's safe, you're staying off the bottom, and not inconveniencing anyone else, your definition of "recreational" should prevail.
One suggestion: you mentioned that you had to look ahead to see your buddy. Especially in low visibility, it's best for buddies to be side-by-side. When buddies swim with one in front of the other in low visibility, there's a good chance of getting separated the first time the trailing buddy stops to look at something interesting.
Best wishes,