Yup I am a no orbit lines person too.
I had a problem recently and for some reason the system kept forgetting my Obit Lines Off setting every time I started and it would put the orbit lines on urgh! Lines everywhere in busy systems, space not empty, noooo couldn't handle it. They fill space that should be empty. now there is vast emptiness and planets and bodies float in space instead of being tied there with a piece of string

Hehe a friend came over that occasionally plays ED and made the comment, "hey why does yours look so much better than mine?...Did they upgrade the graphics recently?" It took him a second or two to realise the only difference was that there were no orbit lines and now he is seeing the objects floating in space instead of surrounded by intersecting lines and circles..
Bill D
- - - Updated - - -
I don't see the point of them once you have the advanced discovery scanner. I only ever really used them to help me find planets in between two orbits when I was exploring with a basic or intermediate scanner. With the ADS everything in the system is pinged and on the Nav panel so there's no reason in my mind to keep the lines on ... screen looks much cleaner without them.
Yes same.... also don't get me started on the advanced discovery scanner, that took the actual skill and fun out of exploration for me.