I understand. I have the relocation brackets myself. I am also 6 feet but have a bit extra in front too. I don't feel the need to raise up but to move back. The relocation brackets do just that. Extra leg room and belly room without sacraficing head room. I have never had the back seat in so it does not bother me to move back more.
For sure the best mod on my Jeep. I don't think I would own a TJ without them. There simply is not enough leg room for me. I'm 6'3".
They do impinge on any back seat passengers you might have. But I rarely have back seat passengers anyway. So it's no biggy.
We have just one son. Who's 19. And he sits behind his mother. She's short. But I put them on the passenger side too. Just so if your going with one other person. They can stretch out and nap if they wanted to. Plus my son is over 6'3". So he has leg room if it's just us too.