When I was into HO, my main objection to "Lionel" was the three rails. I don't know if I am weird or what- but since taking up 3-rail, 2-rail looks weird.
For my O tubular track (used over bridges and in a "coal yard") I added ties, and rattle-can painted all three rails a rail brown color using a cardboard mask with cut-out openings. After painting (before it had a chance to dry) I wiped the tops of the rails using lacquer thinner on a rag. Then ballasted and weathered, mainly using a black wash (again wiping the rails while the wash was wet.)
