Terrain displayed on the map screen

I intended to land on Luna with a lander made of one stage. This meant I would need to save as much fuel on the landing so I had enough on return.
To be as efficient as possible, I attempted a suicide burn. I would be going very close to the ground at periapsis. Long story short, I thought I would be above the terrain. I was wrong. I smashed into a mountain because I couldn’t tell where my orbit clipped the terrain.
This is why we need at least optional 3D planets, so we can plan our landings and expeditions more precisely.