The 8.53° ramps from the One Random Brick Pack might work, but there is only one width and the collision does not actually behave like a ramp.

The 10° ramp from the same is good for driveways, but has only one width of 8x, so road lines aren't possible.

And the 18° (4x length) ramps function well but are too abrupt for any action other than jumping and/or losing control.


BOMP VREEEEM
And the default ramps, of course, are even more abrupt.
I talked to someone who said they could and would do this for me, but that was weeks ago and I don't recall who it was.
Having this is important for many of the things I want to do.