Being able to see, from the Nav Panel, the relative positions of all the bodies in a system unlocked gameplay in supercruise - optimizing my path through a system, avoiding gravity wells, flying curves and doglegs because as well all agree, straight lines are boring.
Not being able to construct that overview without simultaneously obtaining the information on a body removes the gameplay that I enjoyed. I just want to be able to map a system and THEN explore it.
I guess that is a fundamental difference between us. As far as I'm concerned, if I have a "map" of a system, whether it's target data on the Nav Panel or the orbital hierarchy system map, then it has already been explored. If I'm not the one creating the map, then it pretty much negates the main reason I'm out exploring the galaxy in the first place. Creating that map, at first mentally, and then confirming the details of that mental map using the myriad ways it's possible to resolve planets under the new system, is what makes exploring systems fun for me.
Outside the Bubble, Thargoid, and Guardian space, planetary exploration is pretty much a sideshow, which is why I've only been exploring the really interesting planets and moons. Geological and (to a lesser extent) Biological planetary POIs have only so many variations, which is why I keep an eye out for eclipses, which require some rather unique planetary alignments to happen.
If you haven't already, then I really recommend using the FSS as a way to assist navigating to bodies visually. If you want to plot a course through the entire system, try flying straight up out of the orbital plane and then using the FSS to get a better picture of the relative positions of the system's major gravity wells.
The FSS is an active system, so it only gives you the information you tell it to give you. You can use it as much or as little as you need to in order to maximize your fun. The Nav Panel does not "unlock gameplay in Supercruise," it just makes that game play easier by providing you with a lot of high level navigation data. Using less information does require a bit of thinking on your part to optimize your travel path through a system, but that's a good thing, right?