Headroom should be ok imo, just make sure you duck when you enter. And yes, you will be straining your neck to see if the light changed, I do that already and I'm several inches shorter.
But Bart, think of it this way, there's a number of cars growing up that I always vowed to have, but I kept getting taller and taller. It's a little depressing knowing you can afford an Esprit or a TR8 but can't really fit in one. Being tall is nice, but there are drawbacks. However, I can only imagine how being close to 7' limits your vehicle choices.